CHAPTER I

CULTIVATED CHERRIES

CHERRIES AND THEIR KINDRED

The genus Prunus plays a very important part in horticulture. It furnishes, in temperate climates, the stone-fruits, plants of ancient and modern agriculture of which there are a score or more commonly cultivated and at least as many more sparingly grown for their edible fruits. Of these stone-fruits the species of cherries rank with those of the plum and the peach in commercial importance while the several botanical groups of the apricot and almond are less important, but hardly less well-known, members of this notable genus. Prunus is of interest, too, because the history of its edible species follows step by step the history of agriculture. The domestication of its fruits from wild progenitors, most of which are still subjects of common observation, illustrates well the influences and conditions under which plants have generally been brought into domestication. The genus is also of more than ordinary note because the number of its economic species is being increased almost yearly by new-found treasures from North America and Asia, not varieties but species, which promise under future domestication still further to enrich horticulture.

The plum and the peach surpass the cherry in diversity of flavor, aroma, texture, color, form and size, characters which make fruits pleasant to the palate and beautiful to the eye; but the cherry, perhaps, plays a more important part than the plum or the peach in domestic economy. It has fewer prejudices as to soil and climate, hence is much more widely distributed and is more easily grown, being better represented in the orchards and gardens in the regions where the three fruits grow. The cherry, too, fruits more quickly after planting, ripens earlier in the season and its varieties are more regular in bearing and usually more fruitful--characters that greatly commend it to fruit-growing people. Probably it is the most popular of all fruits for the garden, dooryard, roadside and small orchard. All in all, while adorning a somewhat humbler place in pomology, it is more generally useful than the showier and more delicate plum and peach.

Though placed by most botanists in the same genus, each of the stone-fruits constitutes a natural group so distinct that neither botanist nor fruit-grower could possibly take one for another as the trees and fruits of the different groups are called to mind. But there are outstanding forms which seem to establish connections between the many species and the several groups of fruits and through these outliers the characters are so confounded in attempting to separate species that it becomes quickly apparent that there are few distinct lines of cleavage within the genus. For several centuries systematists have disputed as to whether the stone-fruits fall most naturally into one, two, or three genera--indeed have not been able to agree as to whether some species are plums or cherries, or others apricots or plums. Hybridization between the cultivated divisions of the genus--unquestionably it has taken place in nature as well--has added to the perplexities of classification. Accepting, then, for the present at least, the very artificial classification which, rather paradoxically, places in one genus a number of fruits commonly thought of as quite distinct, let us briefly note the characters which best distinguish cherries from their congeners.

The cherry is nearest of kin to the plum. These two are roughly separated from the other cultivated members of the genus to which they belong by bearing their fruits on stems in fascicles while the others are practically stemless and are solitary or borne in pairs. The fruits of plums and cherries are globular or oblong, succulent and smooth or nearly so. Peaches, apricots, nectarines and almonds are more sulcate than plums and cherries and the almond has a drier flesh, splitting at maturity to liberate the stone; and, with the exception of nectarines and a few varieties of apricots, all are very pubescent. The stones of cherries and plums are smooth, or nearly so, while those of the other fruits are sculptured and pitted, though those of the apricot are often somewhat plum-like.

Cherries are separated from plums by their smaller size and distinctive color of skin, juice and flesh; by the texture and distinct flavor of the flesh; by growth in corymbose rather than umbelliferous fascicles; by the more globular stone; and by the arrangement of the leaves in the bud. Leaves of the plum are usually convolute, or rolled up, in the bud, while those of the cherry are conduplicate, or folded lengthwise along the midrib.

We have been discussing the cherries of common cultivation--the Sweet Cherry and Sour Cherry of the orchards, the fascicled cherries to which the botanists give the group name, Cerasus. But there is another group, the Padus cherries, well worthy of brief mention. The most noteworthy representatives of Padus are the bird cherry (_Prunus padus_) of the Old World and the choke cherry (_Prunus virginiana_) of the New World. These Padus cherries are distinguished botanically in having their flowers borne in racemes, that is, in long clusters of which those nearest the base of the shoot open first--rather than in the short-clustered fascicles of the Cerasus group. The cherries are small and almost or quite black. The Padus cherries are but sparingly cultivated but undoubtedly they are capable of some improvement under more thorough cultivation.

DISTRIBUTION OF CULTIVATED CHERRIES

The cherry is one of the most commonly cultivated of all fruits and the many varieties of its several forms encircle the globe in the North Temperate Zone and are being rapidly disseminated throughout the temperate parts of the Southern Hemisphere. For centuries it has been, as we shall see in the history of the species, one of the most valuable fruit-producing trees of Europe and Asia--an inhabitant of nearly every orchard and garden as well as a common roadside tree in temperate climates in both continents. From Europe, as a center of distribution, the cherry has played an important part in the orcharding in temperate regions of other continents. In North America varieties of the cherry are grown from Newfoundland to Vancouver Island on the north, to the Gulf of California, Texas and Florida on the south, yielding fruit in a greater diversity of soils and climates in Canada and the States of the Union than any other tree-fruit.

The Sour Cherry is very cosmopolitan, thriving in many soils; is able to withstand heat, cold and great atmospheric dryness, if the soil contain moisture; and, though it responds to good care, it grows under neglect better than any other tree-fruit. The Sour Cherry, too, is rather less inviting to insects and fungi than most other stone-fruits, being practically immune to the dreaded San José scale. On the other hand the Sweet Cherry is very fastidious as to soils, is lacking in hardiness to both heat and cold and is prey to many insects and subject to all the ills to which stone-fruits are heir; it is grown at its best in but few and comparatively limited areas, though these are very widely distributed.

USES OF THE CHERRY

The cherry is a delectable early-summer fruit, especially grateful as a refreshing dessert and much valued in cookery, when fresh, canned, preserved or dried, for the making of pies, tarts, sauces and confections. During the last few years, in America at least, the consumption of cherries has been enormously increased by the fashion of adding preserved cherries, as much for ornament as to give flavor, to many drinks and ices. The great bulk of the cherry crop now grown in America for commercial purposes is canned, the industry being more or less specialized in a few fruit regions. The demand for cherries for canning seems to be increasing greatly but unfortunately it calls for but few varieties, the Montmorency being the sort sought for among the Sour Cherries, while the hard-fleshed varieties of the Bigarreau type are in greatest demand among the Sweet Cherries.

The cherry, while a very common fruit in nearly all agricultural regions of America, does not hold the place in American markets as a fresh fruit that it does in the towns and cities of Europe. The great abundance of strawberries, raspberries, currants, gooseberries, dewberries, blackberries, as well as early varieties of tree fruits, makes keener here than abroad the competition in the fruit markets during cherry time. The fact, too, that market fruits in America are shipped long distances, for which the cherry is not well adapted, helps to explain the relatively small regard in which this fruit has been held for commercial purposes in the fresh state. In recent years, however, both Sweet Cherries and Sour Cherries, the former in particular, have been sent to the markets in far greater abundance, the impetus to their market value being due to a better product--better varieties, hence greater demand--and to greatly improved facilities for shipping and holding for sale.

In Europe several liqueurs are very commonly made from cherries both for home and commercial uses. Such is not the case in America, where, except in very limited quantities in which unfermented cherry juices are used in the home, this fruit is not used in liqueur-making. In some of the countries of Europe, wine is made from the juice; a spirit, kirschwasser,[1] is distilled from the fermented pulp as an article for both home and commerce; and ratafias and cordials are very generally flavored with cherries. In the Austrian province of Dalmatia a liqueur or cordial called maraschino[2] is made by a secret process of fermentation and distillation. This liqueur is imported in America in considerable quantities to flavor preservatives in which the home-grown cherries are prepared for use in various drinks and confections. No attempts have been made to grow the Marasca cherry on a commercial scale in America but undoubtedly it could be grown and, with the process of making maraschino discovered, an important use would be developed for cherries--all the more to be desired since the foreign maraschino is now grossly adulterated and imitated in this country. Both the fruits and seeds of cherries, especially of the Mahaleb, are steeped in spirits for food, drink and medicinal purposes. An oil used in making perfumes for scenting soaps and confectionery is also extracted from the seeds of the Mahaleb because of which use this species is often called the "Perfumed Cherry."

In the old herbals and pomologies much is made of the value of cherries for medicinal purposes. The fruit was supposed to be a sovereign remedy for various ailments of the digestive tract as well as for nervous disorders and epilepsy. The astringent leaves and bark, or extracts from them, were much used by the ancients in medicine and are still more or less employed both as home remedies and in the practice of medicine as mild tonics and sedatives. One of the active chemicals of the leaf, seed and bark is hydrocyanic acid to which is largely due the peculiar odor of these structures. A gum is secreted from the trunks of cherry trees, known in commerce as cerasin, which has some use in medicine and in various trades as well, especially as a substitute and as an adulterant of gum arabic.

At least three cultivated cherry trees produce wood of considerable value. The wood of the cherry is hard, close-grained, solid, durable, a handsome pale red, or brown tinged with red. _Prunus avium_, the Sweet Cherry, furnishes a wood which, if sufficient care be taken to season it, is of much value in cabinet-making and for the manufacture of musical instruments. _Prunus mahaleb_ is a much smaller tree than the former but its wood, as much as there is of it, is even more valuable, being very hard and fragrant and dark enough in color to take on a beautiful mahogany-like polish. In France the wood of the Mahaleb cherry is held in high esteem, under the name _Bois de St. Lucie_, in cabinet-making and for toys, canes, handles and especially for the making of tobacco pipes. In Japan the wood of _Prunus pseudocerasus_ is said to be in great demand for engraving and in making the blocks used in printing cloth and wall-paper. In America the wood of the orchard species of cherries is seldom used for domestic purposes, that of the wild species being so much more cheaply obtainable and serving all purposes quite as well.

To people who know it only for its fruit, the cherry does not appear particularly desirable as an ornamental. But wild and cultivated cherries furnish many beautiful trees in a genus peculiar for the beauty of its species. The color and abundance of the flowers, fruits and leaves of the cultivated cherries and the fact that they are prolific of forms with double flowers, weeping, fastigiate or other ornamental habits, make the several species of this plant valuable as ornamentals. Besides, they are vigorous and rapid in growth, hardy, easy of culture, comparatively free from pests and adapted to a great diversity of soils and climates. Both the ornamental and the edible cherries are very beautiful in spring when abundantly covered with flowers, which usually open with the unfolding leaves, as well as throughout the summer when overspread with lustrous green foliage and most of them are quite as conspicuously beautiful in the autumn when the leaves turn from green to light and dark tints of red. All will agree that a cherry tree in full fruit is a most beautiful object. In the winter when the leaves have fallen, some of the trees, especially of the ornamental varieties, are very graceful and beautiful, others are often picturesque, and even the somewhat stiff and formal Sweet Cherries are attractive plants in the garden or along the roadside.

Very acceptable jellies, sauces and preserves are made from several of the wild cherries in the Padus group. The peasantry of the Eastern Hemisphere have in times of need found them important foods as have also the American Indians at all times. The fruits of some of the species of Padus are quite commonly used in flavoring liqueurs and on both continents are sometimes fermented and distilled into a liqueur similar to kirschwasser. The bark of different parts of the trees of this group is valuable in medicine--at least is largely used. The trees of several species form handsome ornamentals and some of them are in commerce for the purpose. _Prunus serotina_, one of the group, because of the strength of its wood and the beautiful satiny polish which its surface is capable of receiving, is a valuable timber tree of American forests. For the products of the members of this group, as just set forth, the domestication of some of the species of Padus might well be pushed.

[1] Kirschwasser as a commercial article is made chiefly on the upper Rhine from the wild black Sweet Cherry (_Prunus avium_). In its manufacture, fruit--flesh and kernels--is mashed into a pulp which is allowed to ferment. By distillation from this fermented pulp a colorless liqueur is obtained.

[2] Maraschino is a liqueur, or cordial, made from the fruit and leaves of the small, sour, black Marasca cherry. The product comes chiefly from Zara, the capital of the Austrian province of Dalmatia, where it has been made and exported for over 200 years. Such accounts of the process of making maraschino as have become public seem to agree that the liqueur is a distillation of a compote made from the fruit and young leaves. When ripe the cherries are picked early in the morning and sent at once to the distillery where the stones are extracted by machinery. The leaves are cut, pressed and added to the fruit with sugar and alcohol. This mixture is allowed to ferment for six months or thereabouts and from it is then distilled maraschino. It is then stored in cellars for three years before being placed on the markets. In both Europe and America there are many imitations of the maraschino liqueur in which neither fruit nor foliage of the Marasca nor any other cherry has any part.

According to the Dalmatians all attempts to improve the Marasca cherry by culture have failed. They say, too, that it will not thrive elsewhere than in Dalmatia. Under culture, the fruits and leaves lose their distinctive aroma and taste as they do on any but the native soil of the variety. The poorer, sparser and more rocky the ferruginous soil, the wilder the tree, the smaller and sourer the cherries, the better the maraschino liqueur--so the present makers say.

Since considerable quantities of cherries are put up in America in maraschino, or its imitation, and the manufacture of such products is a growing industry, the following ruling by the Board of Food and Drug Inspection of the United States Department of Agriculture, taken from Food Inspection Decision 141, is of interest to growers, canners and users of cherries:

"In considering the products prepared from the large light-colored cherry of the Napoleon Bigarreau, or Royal Anne type, which are artificially colored and flavored and put up in a sugar sirup, flavored with various materials, the Board has reached the conclusion that this product is not properly entitled to be called 'Maraschino Cherries,' or 'Cherries in Maraschino.' If, however, these cherries are packed in a sirup, flavored with maraschino alone, it is the opinion of the Board that they would not be misbranded, if labeled 'Cherries, Maraschino Flavor,' or 'Maraschino Flavored Cherries.' If these cherries are packed in maraschino liqueur there would be no objection to the phrase 'Cherries in Maraschino.' When these artificially colored cherries are put up in a sirup flavored in imitation of maraschino, even though the flavoring may consist in part of maraschino, it would not be proper to use the word 'Maraschino' in connection with the product unless preceded by the word 'Imitation.' They may, however, be labeled to show that they are a preserved cherry, artificially colored and flavored.

"The presence of artificial coloring or flavoring matter, of any substitute for cane sugar, and the presence and amount of benzoate of soda, when used in these products must be plainly stated upon the label in the manner provided in Food Inspection Decisions Nos. 52 and 104."

LITERATURE OF THE CHERRY

Despite the important part they have played in orcharding since the domestication of fruits in temperate zones, as shown by their history and their present popularity, pomological writers have singularly neglected cherries. There are relatively few European books devoted to them and in America, while there are treatises on all others of the common tree-fruits, the cherry alone seems not to have inspired some pomologist to print a book. Neither are the discussions in general pomologies as full and accurate as for other fruits. The reason for this neglect is that the cherry, until the last decade or two, has scarcely been a fruit of commerce, having been grown almost entirely for home use or at most for the local market. As a result of this neglect of the cherry by students of pomology, we have no authoritative nor serviceable system of classification of the varieties of cherries and the nomenclature of this fruit is in an appalling state of confusion, as a glance at the synonymy of some of the older varieties discussed in _The Cherries of New York_ will show.

AMELIORATION OF THE CHERRY

The amelioration of the cherry has been in progress almost since the dawn of civilization, yet few men have directed their efforts toward the improvement of this fruit. The histories of the varieties described in _The Cherries of New York_ show that nearly all of them have come from chance seedlings. Possibly there has been little interest in improving cherries because this fruit is comparatively immutable in its characters.

In spite of the fact that there are a great number of varieties, 1,145 being described in _The Cherries of New York_, this of all stone-fruits is most fixed in its characters. The differences between tree and fruit in the many varieties are less marked than in the other fruits of Prunus and the varieties come more nearly true to seed. Though probably domesticated as long ago as any other of the tree-fruits, the cherry is now most of all like its wild progenitors. The plum is very closely related to the cherry but it has varied in nature and under cultivation much more than the cherry and in accordance with different environments has developed more marked differences in its species to endure the conditions brought about by the topographical and climatic changes through which the earth has passed. Under domestication more than twice as many orchard varieties of the plum have come into being as of the cherry. In spite of this stability, there are ample rewards in breeding cherries to those who will put in practice rightly directed efforts to improve this fruit--a statement substantiated by the histories of some of the best varieties, described later in this text, which were originated through what was passing as current coin in plant-breeding before the far better methods of the present time, brought about by Mendel's discovery, came into being.

The cherry, as the histories of its many diverse kinds show, has been improved only through new varieties. There is no evidence, whatever, to show that any one of the several hundred cherries described in this text has been improved by selection as a cumulative process, or, on the other hand, that any one of them has cumulatively degenerated. Of varieties cultivated for their fruits there are no records of mutations either from the seed or from bud, though of the ornamental cherries not a few have arisen as bud-mutations, as, for example, the several double-flowered cherries and those of weeping or fastigiate habit of growth and the many sorts with abnormally colored foliage. Since improvement depends upon the bringing into being of new cherries it becomes highly important to know how the varieties we are dealing with in _The Cherries of New York_ have come into existence. The following is a summary of their manner of origin:--

No case is recorded in _The Cherries of New York_ of a variety known to have come from self-fertilized seed.

The seed parent is given for 61 varieties. The statements as to seed parents are probably accurate, for a man planting cherry seeds would record the name of the seed parent correctly if he knew it.

The seed and pollen parents of twenty of the cherries described in this work are given. Sixteen of these are hybrids originating with Professor N. E. Hansen of South Dakota, leaving but four sorts the parents of which were known before the recent work of Professor Hansen.

No cherry cultivated for its fruit is reported to have come from a sport or a bud-mutation.

Cherries arising from seed sown without knowledge of either parent or from natural seedlings are put down as chance seedlings; of these there are 147.

The origin of 917 of the varieties here described is unknown.

The total number of cherries under discussion is 1,145.

To improve the cherry the breeder must know the material with which he is working. The following is a brief discussion of the characters of this fruit to be found in the technical descriptions of species and varieties.

TREE AND FRUIT CHARACTERS OF THE CHERRY

Species of cherries have very characteristic trees. The merest glance at the tree enables one to tell the Sweet Cherry, _Prunus avium_, from the Sour Cherry, _Prunus cerasus_. The first named is the larger of the two, especially reaching a greater height, is pyramidal in shape, with branches erect and bearing much less foliage than the Sour Cherry. The Sweet Cherry often lives for a century or more--the Sour Cherry attains but the three score years and ten of man. _Prunus cerasus_ is easily distinguished from _Prunus avium_ by its comparatively low, roundish and never pyramidal head. So, too, many of the varieties of either of these two species are readily told in the orchard by the size or habit of the plant. Other species are either shrubby or tree-like and their varieties may often be identified from the spaciousness or dwarfness of its trees. Size is rather more variable than other gross characters because of the influence of environment--food, moisture, light, isolation, pests and the like--yet size in a plant, or in the parts of a plant, is a very reliable character when proper allowances have been made for environment.

Habit of growth, unlike size, varies but little with changing conditions and thus becomes a most important means of distinguishing species and varieties and not infrequently sets the seal and sign of desirability for an orchard cherry. More than any other character, habit of growth gives what is called "aspect" to a cherry tree. Thus, a species or a variety may be upright, spreading, round-topped, drooping or weeping in habit of growth; the head may be open or dense and may be formed by a central shaft with several whorls of branches or by three or four trunk-like stems each with its scaffolding branches. The trees may grow rapidly or slowly and may be long-lived or short-lived. The trunks may be short and stocky, or long and slender, straight or crooked, gnarled or smooth, these characters often determining whether a cherry is manageable or unmanageable in the orchard.

The degree of hardiness is a very important diagnostic character for groups of cherries and often wholly indicates their value for agriculture. Thus, the varieties of _Prunus avium_ are but little hardier than the peach while those of _Prunus cerasus_ are as hardy or hardier than the apple. The range of varieties as to hardiness falls within that of the species and it is interesting to note that in Europe, where the wild _Prunus avium_ is very common, in the many centuries since the fruit has been under domestication, a cultivated variety hardier than the wild Sweet Cherry has not been developed. Cherries are designated in the technical descriptions as hardy, half-hardy and tender.

Productiveness, age of bearing, and regularity of bearing are distinctive and valuable characters of orchard cherries but not of wild cherries. The care given the tree greatly influences fruitfulness, yet the quantity of fruit produced is often a helpful means of identifying a variety and is a character that must always be considered by the plant-breeder. Age of bearing and regularity of bearing are most important characters with the pome fruits, the apple, in particular, but while worth considering with the drupes are of relatively little value, all drupaceous fruits coming in bearing at about the same time for the species and all bearing regularly, as a rule, unless interfered with by some outside agency preventing the setting or causing the dropping of fruit.

Immunity and susceptibility to diseases and insects are valuable taxonomic characters of both species and varieties of cultivated cherries. Thus, the varieties of _Prunus cerasus_ are very susceptible to black knot (_Plowrightia morbosa_), while those of _Prunus avium_ are almost immune. On the other hand, _Prunus avium_ is an inviting prey to San José scale (_Aspidiotus perniciosus_), while _Prunus cerasus_ is but little injured, indeed, seldom attacked; _Prunus mahaleb_ appears to be almost wholly immune to the powdery mildew (_Podosphaera oxyacanthae_), while _Prunus avium_ and _Prunus cerasus_ are much attacked, though Wood, a variety of _Prunus avium_, is almost immune. The English Morello, a variety of _Prunus cerasus_, is very subject to leaf spot (_Cylindrosporium padi_), while Montmorency, of the same species, is nearly immune. These examples can be multiplied many times by references to the discussions of varieties, and represent only observations on the grounds and in the neighborhood of this Station. They serve to show the great importance, to the fruit-grower, the plant-breeder and the systematist, of natural resistance to disease and insects.

Both the outer and the inner bark have considerable value in determining species but are of little importance in identifying varieties and have no economic value to the fruit-grower and hence but little to the breeder. Smoothness, color, thickness and manner of exfoliation are the attributes of the outer bark to be noted, while the color of the inner bark is the only determinant and that relatively unimportant. In young trees the bark of the cherry of all species is smooth, glossy or even brilliant; but later it becomes uneven, scaly and dull, usually ash-gray but varying in all of these characters to an extent well worth noting for taxonomic purposes. Cherries, in common with most trees, have a lighter colored bark in cold than in warm regions, and in dry than in wet areas.

Branches and branchlets are very characteristic in both species and varieties. The length, thickness, direction, rigidity and the branching angle are valuable determining characters and very stable ones, changing but little even with marked variations of soil and climate. Thus, a Sweet Cherry tree can be told from a tree of the Sour Cherry, or the English Morello can be distinguished from Montmorency by branch characters as far as the outlines of the trees are discernible. Few cherries bear spines but all are more or less spurred and these spurs are quite characteristic even in varieties. With the branchlets the length of the internodes should be considered and their direction, whether straight or zigzag; also color, smoothness, amount of pubescence, size and appearance of the lenticels, the presence of excrescences, are all to be noted in careful study though all are more or less variable, pubescence especially so, this character being too often relied upon in descriptions by European botanists and pomologists.

Leaf-buds vary greatly in different species in size, shape, color of the buds and of their outer and inner scales and in the outline of the scales. The angle at which the bud stands out from the branchlet is of some taxonomic value. Vernation, or the disposition of the leaf-blade in the bud, is a fine mark of distinction in separating the cherry from other stone-fruits and while all cherry leaves are supposed to be conduplicate, that is, folded by the midrib so that the two halves are face to face, yet there are slight but important differences in the conduplication of the leaves in both species and varieties. The manner of bearing buds--whether single, in pairs, or in rosettes--must be taken into account, with species at least, and differences in shape and position of leaf and fruit-buds must be noted.

Leaves in their season are very evident and either collectively or individually are valuable determinants of species and varieties. Fruit-growers take little note of leaves, however, though they should be taken into practical account, since their size and number often indicate the degree of vigor. The variability of leaves is usually within limits easily set and occurs most often in young plants, in extremes of soil and climate, and on very succulent growths or water-sprouts. Leaf-size is the most variable character of this organ but is yet dependable in separating several species, as, for example, _Prunus avium_ from _Prunus cerasus_, the leaves being very much larger in the former than in the latter species. Leaf-forms are very constant in species and varieties, hence especially valuable in classification.

Much care has been taken to illustrate accurately the size and form of cherry leaves in the color-plates in this text but it is impossible to reproduce by color-printing the tints of the leaves, though these are quite constant in both species and varieties.

Other characters of leaves taken into account in describing cherries are thickness, roughness, and pubescence, all of which are somewhat variable, being greatly influenced by climate and soil. Quite too much stress is laid upon the value of pubescence on leaves in determining groups, unless comparisons can be made between plants growing in the same habitat. Possibly more important than any other part of the leaf-blade, in the study of species at least, is the margin. This in the cherry is always serrated and often sub-serrated. These serrations are best studied at the middle of the sides of the leaves, those at the base and apex often being crowded or wanting.

The petiole may be used to good advantage in distinguishing both species and varieties. Thus, in consequence of the great length and slenderness of the petiole of leaves of Sweet Cherries, the leaves are always more or less drooping, while those of the Sour Cherry are usually erect by reason of the petiole being short and strong. The color of the petiole is said by some to be correlated with that of the fruit--a statement that needs verification. The pubescence of the petiole must be noted.

The position, size, shape and color of the glands on cherry leaves must be noted as they are fairly constant guides. They are usually on the petiole at the base of the leaf but are sometimes on the leaf itself. The glands are commonly given as globular or reniform in shape but there are often intermediate forms the shape of which is hard to classify.

Stipules in this plant have considerable taxonomic value, having some distinguishing marks not possessed by the leaves. Cherry leaves springing from dormant leaf-buds have very small stipules, sometimes so minute as hardly to be seen, but on the current year's growth the stipules are larger, being largest at the tip of the branchlet. There is considerable difference in the size of these organs in varieties of the same species. Stipules of the cherry are nearly always borne in pairs. The small stipules, appearing with the first leaves, drop, at this Station, about the middle of June while those accompanying the later leaves on the wood growth of the current year remain until in July, there being a difference in varieties as to how long they remain. All stipules are deeply toothed and bear glands of varying color and shape on the serrations, the characters of both serrations and glands offering some distinguishing marks for species and varieties.

The flowers of cherries are very characteristic, as a study of the color-plates of blossoms will show, furnishing a wholly distinctive mark of species and helping to distinguish varieties. The flowers are hermaphrodites and are borne in more or less dense, corymbose clusters. Individual flowers in species and varieties vary in size, shape, color and odor. The peduncles are long or short, as the case may be; the corolla furnishes distinctions in size, shape and color of petals; the calyces are chiefly distinguished by their glands and the amount and character of the pubescence; while stamens and pistils offer differences in size, color of their different parts and in the number of stamens. In plums the reproductive organs differ greatly in ability to perform their functions, some varieties being self-sterile. In New York there seem to be no marked differences in fecundity in cherries nor are there so frequently the malformations of reproductive organs which are found in plums. The season of flowering is a fine mark of distinction between species and varieties, a fact well brought out by the chart on pages 80-81.

Of all organs, the fruit of the cherry is most responsive to changed conditions and hence most variable, yet the fruits furnish very valuable taxonomic characters in both botany and pomology. In pomology, in particular, the fruits must be closely studied. Size, shape, color, bloom, stem, cavity, apex, suture and skin are the outward characters of which note must be made; while the color, aroma, flavor and texture of the flesh are usually very characteristic. Both species and varieties are well distinguished by the time of ripening though there is much variation in ripening dates. The keeping quality is scarcely taken into account with cherries but varies a great deal, chiefly in accordance with firmness of the flesh. The flesh of cherries, as in all drupaceous fruits, clings to the stone or is wholly or partly free--a character of interest both to the systematist and to the fruit-grower. The color of the juice, whether colorless or red, is a plain and certain dividing line in both species and varieties.

The pits of cherries are rather more lacking in distinction than in other stone-fruits, plums for example, yet they must be accounted of considerable value in determination and for this reason have been included in all of the color-plates of varieties. Cherry-pits from individual trees are almost lacking in differences except in size but between species and varieties show many distinctions not only in size but in shape, surfaces, grooves and ridges, in the ends and more or less in the seeds within. Cherries of any variety grown on poor soils or in incongenial climates tend to have large stones and little flesh, while the pits are smaller and there is more flesh with the opposite extremes in environment. As will be pointed out in the discussion of the group of cherries known as the Dukes, many varieties have pits with shrunken and abortive seeds coming, as we think, from the hybrid origin of these cherries.

The several pages given to the discussion of the characters of cherries are in preparation for a proper understanding of the classifications and descriptions of species and varieties. We are now ready for the classification of the species of cherries which contribute or may contribute forms for cultivation either for their fruits or as stocks upon which to grow edible cherries. The following is a brief conspectus of the edible species of Prunus followed by a fuller conspectus of the sub-genus Cerasus to which cherries belong.

A CLASSIFICATION OF CULTIVATED CHERRIES

The genus Prunus is variously delimited and divided by systematic botanists. A simple, and from a horticultural point of view, a very satisfactory classification, is to put almonds and peaches in one sub-genus (Amygdalus), cherries in a second (Cerasus), plums and apricots in a third (Euprunus), and to place the racemose cherries and cherry-laurels, usually considered in Prunus, in another genus, Padus. In this division of Prunus into three sub-genera we may assign to each the following characters.

A. Leaves convolute, _i. e._, rolled in the bud (showing best in the opening buds).[3]

_Euprunus._ Plums and apricots.

A.A. Leaves conduplicate, _i. e._, folded lengthwise along the midrib in the bud.

B. Fruit more or less dry and hirsute; if juicy or glabrous the blossoms appear long before the opening of the leaves; fruits without stems.

_Amygdalus._ Almonds and peaches.

B.B. Fruit always juicy and usually glabrous; blooms appearing with the leaves.

_Cerasus._ Cherries.

Of these several divisions we are here concerned only with Cerasus, to which belong all fascicled cherries, the racemose, or Padus, cherries as yet having little or no value as esculents. The genus Prunus is from year to year being enlarged by the discovery of new species, the additions to Cerasus in particular being numerous. Thus, a decade ago, botanists placed in this sub-genus, at the outside, not more than a score of species but Koehne, the most recent monographer of Cerasus, describes 119 species. Of Koehne's species at least a dozen are more or less cultivated for their fruits and a score or more are grown as ornamentals.

The following species are listed by Koehne:[4]

SPECIES OF CHERRIES

Div. I. TYPOCERASUS Koehne.

Sect. 1 CREMASTOSEPALUM Koehne.

Subsect. 1. MAHALEB Koehne.

_Cerasus_ sect. _Mahaleb_ Roemer. _Fam. Nat. Syn._ =3=:79. 1847.

_Prunus_ subgen. _Cerasus_ sect. _Mahaleb_ Koehne. _Deutsche Dendr._ 305. 1893.

Ser. 1. EUMAHALEB Koehne.

=1. Prunus mahaleb= Linnaeus. _Sp. Pl._ 472. 1753. Europe, Western Asia.

Ser. 2. PARAMAHALEB Koehne.

=2. Prunus mollis= Walpers. _Rep._ =2=:9. Western North America.

=3. Prunus emarginata= Walpers. _Rep._ =2=:9. Western North America.

_Cerasus californica_ Greene. _Fl. Francis_ =1=:50.

=4. Prunus pennsylvanica= Linnaeus. _Syst._ ed 13 Suppl. 252. Eastern North America.

Subsect. 2. EUCERASUS Koehne.

_Prunus_ sect. _Eucerasus_ Koehne. _Deutsche Dendr._ 306. 1893.

=5. Prunus fruticosa= Pallas. _Fl. Ross._ =1=:19. 1784. Europe to Siberia.

=6. Prunus acida= C. Koch. _Dendr._ =1=:112. 1869. Southern Europe.

=7. Prunus cerasus= Linnaeus. _Sp. Pl_. 474. 1753. Europe, Western Asia.

=8. Prunus avium= Linnaeus. _Fl. Svec._ ed =2=:165. 1755. Europe, Western Asia.

Subsect. 3. PHYLLOMAHALEB Koehne.

Ser. 1. APHANADENIUM KOEHNE.

=9. Prunus maximowiczii= Ruprecht. _Bul. Acad. Sci. St. Pétersburg_ =15=:131. 1857.

_Prunus bracteata_ Franchet & Savatier. _Enum. Pl. Jap_. =2=:329. 1879.

_Prunus apetala_ Zabel. _Mitt. Deutsch. Dendr. Ges._ =13=:60 (not Franchet & Savatier) 1904. Amur, eastern Manchuria, Korea, Saghalin, Japan from Hokkaido to Kiushiu.

=Prunus maximowiczii= aperta Komarow. _Act. Hort. Petrop._ =22=:5, 48. 1904. Manchuria from the Ussuri through Kirin to Mukden and northern Korea

=10. Prunus pulchella= Koehne. _Plant. Wils._ Pt. =2=:197. 1912. Western Hupeh.

Ser. 2. MACRADENIUM Koehne.

=11. Prunus conadenia= Koehne. _l. c._ 197. Western Szechuan.

=12. Prunus pleiocerasus= Koehne. _l. c._ 198. Western Szechuan.

=13. Prunus macradenia= Koehne. _l. c._ 199. Western Szechuan.

=14. Prunus discadenia= Koehne. _l. c._ 200. Western Hupeh.

=15. Prunus szechuanica= Batalin. _Act. Hort. Petrop._ =14=:167. 1895. Szechuan.

Subsect. 4. PHYLLOCERASUS Koehne.

=16. Prunus tatsienensis= Batalin. _Act. Hort. Petrop._ =14=:322. 1897. Szechuan.

=Prunus tatsienensis= adenophora (Franchet) Koehne. _Plant. Wils._ Pt. =2=:238. 1912.

_Prunus maximowiczii adenophora_ Franchet. _Pl. Delavay._ 195. 1889. Yunnan.

=Prunus tatsienensis= stenadenia Koehne. _Plant. Wils._ Pt. =2=:201. 1912. Western Szechuan.

=17. Prunus variabilis= Koehne. _l. c._ 201. Western Hupeh.

=18. Prunus pilosiuscula= (Schneider) Koehne. _l. c._ 202.

_Prunus tatsienensis pilosiuscula_ Schneider. Fedde _Rep. Nov. Sp._ =1=:66. 1905. Western Hupeh and Szechuan.

=19. Prunus polytricha= Koehne. _Plant. Wils._ Pt. =2=:204. 1912. Western Hupeh.

=20. Prunus rehderiana= Koehne. _l. c._ 205. Western Hupeh.

=21. Prunus venusta= Koehne. _l. c._ 239. Western Hupeh.

=22. Prunus litigiosa= Schneider. Fedde _Rep. Nov. Sp._ =1=:65. 1905. Hupeh.

=Prunus litigiosa abbreviata= Koehne. _Plant. Wils._ Pt. =2=:205. 1912. Western Hupeh.

=23. Prunus clarofolia= Schneider. Fedde _Rep. Nov. Sp._ =1=:67. 1905. Szechuan.

Subsect. 5. PSEUDOMAHALEB Koehne.

=24. Prunus yunnanensis= Franchet. _Pl. Delavay._ 195. 1889. Yunnan.

=25. Prunus macgregoriana= Koehne. _Plant. Wils._ =Pt. 2:=240. 1912. Western Hupeh.

=26. Prunus henryi= (Schneider) Koehne. _l. c._ 240.

_Prunus yunnanensis henryi_ C. K. Schneider. Fedde _Rep. Nov. Sp._ =1:=66 (in part) 1905. Yunnan.

=27. Prunus neglecta= Koehne. _Plant. Wils._ =Pt. 2:=241. 1912.

_Prunus yunnanensis henryi_ C. K. Schneider. Fedde _Rep. Nov. Sp._ =1:=66 (in part) 1905. Yunnan.

Subsect. 6. LOBOPETALUM Koehne.

Ser. 1. HETEROCALYX Koehne.

=28. Prunus scopulorum= Koehne. _Plant. Wils._ =Pt. 2:=241. 1912. Western Hupeh.

=29. Prunus glabra= (Pampanini) Koehne.

_Prunus hirtipes glabra_ Pampanini. _Nuov. Giorn. Bot. Ital._ =17=:293. 1910; =18:=122. 1911. Hupeh.

=30. Prunus involucrata= Koehne. _Plant. Wils._ =Pt. 2:=206. 1912. Western Hupeh.

=31. Prunus hirtipes= Hemsley. _Jour. Linn. Soc._ =23:=218. 1887.

=32. Prunus schneideriana= Koehne. _Plant. Wils._ =Pt. 2:=242. 1912. Chekiang.

=33. Prunus duclouxii= Koehne. _l. c._ 242. Yunnan.

=34. Prunus ampla= Koehne. _Plant. Wils._ =Pt. 2:=243. 1912. Szechuan.

=35. Prunus malifolia= Koehne. _l. c._ 207. Western Hupeh.

=Prunus malifolia rosthornii= Koehne. _l. c._ 243. Szechuan.

Ser. 2. CYCLAMINIUM Koehne.

=36. Prunus cyclamina= Koehne. _Plant. Wils._ =Pt. 2:=207. 1912. Western Hupeh.

=Prunus cyclamina biflora= Koehne. _l. c._ 243. Western China.

=37. Prunus dielsiana= Schneider. Fedde _Rep. Nov. Sp._ =1:=68. 1905.

"_P. szechuanica_, var.?" or "_P. szechuanica dielsiana_ Schneider," _l. c._, not _P. szechuanica_ Batalin. Hupeh.

=Prunus dielsiana laxa= Koehne. _Plant. Wils._ =Pt. 2:=208. 1912. Western Hupeh.

=Prunus dielsiana conferta= Koehne. _l. c._ 244. Western Hupeh.

=38. Prunus plurinervis= Koehne. _l. c._ 208. Western Szechuan.

=39. Prunus rufoides= Schneider. Fedde _Rep. Nov. Sp._ =1:=55. 1905. Szechuan.

=40. Prunus hirtifolia= Koehne. _Plant. Wils._ =Pt. 2:=209. 1912. Western Szechuan.

Sect. 2. =PSEUDOCERASUS= Koehne.

_Prunus_ subgen. _Cerasus_ sect. _Yamasakura_ Koidzumi. _Tokyo Bot. Mag._ =25=:183. 1911.

Subsect. 7. HYPADENIUM Koehne.

=41. Prunus glandulifolia= Ruprecht & Maximowicz. _Mém. Sav. Étr. Acad. Sci. St. Pétersburg_ =9:=87 (_Prim. Fl. Amur._) 1859. Amur.

Subsect. 8. SARGENTIELLA Koehne.

=42. Prunus pseudocerasus= Lindley. _Trans. Hort. Soc. Lond._ =6:=90. 1826. Cultivated in China.

_Cerasus pseudocerasus_ G. Don. Loudon _Hort. Brit._ 200. 1830.

_Prunus sieboldii_ Koidzumi. _Tokyo Bot. Mag._ =25:=184. 1911.

=Prunus pseudocerasus sieboldii= Maximowicz. _Bul. Acad. Sci. St. Pétersburg_ =29:=102.

_Prunus paniculata_ Ker. _Bot. Reg._ =10:= t. 800. 1824, not _Prunus paniculata_ Thunberg.

_Cerasus paniculata_ De Candolle. _Prodr._ =2:=539. 1825.

_Cerasus sieboldtii_ Carrière. _Rev. Hort._ 371. 1866.

_Prunus sieboldii_ Wittmack. _Gartenfl._ =51:=272. 1902.

_Prunus pseudocerasus serrulata sieboldtii_ Makino. _Tokyo Bot. Mag._ =22:=102. 1908?

_Prunus serrulata serrulata sieboldtii_ Makino. _l. c._ =23:=74. 1909.

_Prunus pseudocerasus typica sieboldii_ Koidzumi. _l. c._ 182.

_Prunus pseudocerasus flore roseo pleno_ Koehne. (Horticultural)

_Prunus pseudocerasus naden_ Koehne. (Horticultural)

=Prunus pseudocerasus watereri= Koehne. _l. c._ 172. 1909.

_Cerasus wattererii_, cited by Lavallée _Icon. Arb. Segrez._ 119. 1885, as a synonym under _Cerasus pseudocerasus_?

_Cerasus watereri_ Goldring. _Garden_ =33:=416, fig. p. 420. 1888?

_Prunus serrulata serrulata wattererii_ Makino. _Tokyo Bot. Mag._ =23:=75. 1909? (Horticultural)

=Prunus pseudocerasus virescens= Koehne.

_Prunus donarium_ Siebold. Rijks-Herbarium, Leyden.

=43. Prunus paracerasus= Koehne. Fedde _Rep. Nov. Sp._ =7:=133. 1909. Japan. (Horticultural)

=44. Prunus serrulata= Lindley. _Trans. Hort. Soc. London_ =7=:138. 1830.

_Prunus cerasus flore simplici_ Thunberg. _Fl. Jap._ 201. 1784.

_Prunus donarium_ Siebold. _Verh. Batav. Genoot._ =12:= No. 1. 68 (_Syn. Pl. Oecon._) 1827.

_Prunus jamasakura_ Siebold. _l. c._ 1827.

_Cerasus serrulata_ G. Don. Loudon _Hort. Brit_. 480. 1830.

_Prunus puddum_ Miquel. _Ann. Mus. Lugd.-Bat._ =2=:90, (in part, not Wallich) 1865.

_Prunus pseudocerasus jamasakura glabra_ Makino. _Tokyo Bot. Mag._ =22=:93. 1809.

_Prunus pseudocerasus jamasakura præcox_ Makino. _l. c._ 98. 1908.

_Prunus pseudocerasus jamasakura glabra præcox_ Makino. _l. c._ 113.

_Prunus pseudocerasus serrulata glabra_ Makino. _l. c._ 101.

_Prunus pseudocerasus spontanea hortensis_ Koidzumi. _l. c._ =23=:183. 1909.

_Prunus cerasus flore pleno_ Thunberg. _Fl. Jap._ 201. 1784.

_Prunus serrulata_ Lindley. cf. supra.

_Cerasus serrulata_ G. Don. Loudon Arb. Brit. =2=:701, fig. 407. 1833.

_Cerasus pseudocerasus_ Lavallée. _Icon. Arb. Segrez._ 119, t. 36. 1885, (ubi citatur: _Cerasus maeda_ h.).

_Prunus pseudocerasus serrulata glabra fugenzo_ Makino. _Tokyo Bot. Mag._ =22=:73. 1908.

_Prunus serrulata serrulata fugenzo rosea_ Makino. _l. c._ =23=:74. 1909.

_Prunus jamasakura elegans glabra_ Koidzumi. _l. c._ =25=:185. 1911.

_Prunus jamasakura speciosa_ Koidzumi. _l. c._ 186. Japan, Korea.

=Prunus serrulata albida= (Makino) Koehne.

_Prunus pseudocerasus hortensis flore simplici albo_ Maximowicz. _Bul. Acad. Sci. St. Pétersburg_ =29=:102.

_Prunus pseudocerasus_ Stapf. _Bot. Mag._ 131: t. 8012. 1905.

_Prunus pseudocerasus serrulata sieboldii albida_ Makino. _Tokyo Bot. Mag._ =22=:102. 1908.

_Prunus serrulata serrulata albida_ Makino. _l. c._ =23=:74. 1909.

_Prunus serrulata yashino_ Koehne. _Mitt. Deutsch. Dendr. Ges._ =18=:167. 1909.

_Prunus pseudocerasus yoshino_ Koehne. (Horticultural)

=Prunus serrulata lannesiana= (Carrière) Koehne. _Mitt. Deutsch. Dendr. Ges._ =18=:167. 1909.

_Cerasus lannesiana_ Carrière. _Rev. Hort._ 198. 1872.

_Prunus pseudocerasus hortensis flore simplici carneo_ Maximowicz. _Bul. Acad. Sci. St. Pétersburg_ =29=:102.

_Prunus serrulata serrulata lannesiana_ Makino. _Tokyo Bot. Mag._ =23=:74. 1909.

_Prunus jamasakura speciosa nobilis_ Koidzumi. _l. c._ =25=:187. 1911.

=Prunus serrulata kriegeri= Koehne. _Gartenfl._ =52=:2 (nomen nudum) 1902.

_Cerasus pendula kriegeri_ F. Späth ex Koehne.

=Prunus serrulata grandiflora= A. Wagner. _Gartenfl._ =52=:169, t. 1513a. 1903.

_Prunus pseudocerasus hortensis flore pleno viridi_ Maximowicz. _Bul. Acad. Sci. St. Pétersburg_ =29=:102.

_Prunus pseudocerasus serrulata glabra viridiflora_ Makino. _Tokyo Bot. Mag._ =22=:102 1908.

_Prunus serrulata serrulata viridiflora_ Makino. _l. c._ =23=:74. 1909.

_Cerasus donarium_ Siebold. Rijks-Herbarium, Leyden.

_Prunus pseudocerasus ukon_ Koehne. (Horticultural)

=Prunus serrulata ochichima= Koehne. _Mitt. Deutsch. Dendr. Ges._ =18=:169. 1909.

_Prunus serrulata serrulata fugenzo, 2. alborosea_ Makino. _Tokyo Bot. Mag._ =23=:74. 1909.

_Prunus pseudocerasus ochichima_ Koehne. (Horticultural)

_Prunus pseudocerasus shirofugen_ Koehne. (Horticultural)

=Prunus serrulata hisakura= Koehne. _Gartenfl_. =51=:2, t. 1494 b. 1902.

_Cerasus caproniana flore roseo pleno_ Van Houtte. _Fl. des. Serres_ =21=:141, t. 2238. 1875.

_Cerasus serratifolia rosea_ Carrière. _Rev. Hort._ 889, t. fig. B. 1877.

_Prunus pseudocerasus hortensis flore semipleno roseo_ Maximowicz. _Bul. Acad. Sci. St. Pétersburg_ =11=:699. 1883.

_Prunus pseudocerasus hisakura_ Koehne. (Horticultural)

_Prunus pseudocerasus benifugen_ Koehne. (Horticultural)

_Prunus pseudocerasus "New Red_." Koehne. (Horticultural)

_Prunus serrulata "W. Kou."_ Koehne. (Horticultural)

_Prunus jamasakura speciosa nobilis donarium_ Koidzumi. _Tokyo Bot. Mag._ =25=:187. 1911.

=Prunus serrulata veitchiana= Koehne. Fedde _Rep. Nov. Sp._ =9=:122. 1911.

_Cerasus pseudocerasus "James Veitch." Gartenfl._ =51=:497. 1902. (Horticultural)

=Prunus serrulata mucronata= Koehne. _Mitt. Deutsch. Dendr. Ges._ =18=:170. 1909.

_Prunus pseudocerasus hortensis flore pulcherrimo pleno candido_ Maximowicz. _Bul. Acad. Sci. St. Pétersburg_ =29=:102.

_Prunus cerasus flore roseo pleno_ Koehne. (Horticultural)

_Prunus serrulata flore pleno_ Koehne. (Horticultural)

=Prunus serrulata shidare-sakura= Koehne. _Mitt. Deutsch. Dendr. Ges._ =18=:170. 1909.

_Prunus pseudocerasus hortensis flore carneo suffuso_ Maximowicz. _Bul. Acad. Sci. St. Pétersburg_ =29=:102.

_Prunus pseudocerasus shidare-sakura_ Koehne. (Horticultural)

44 × 88? =Prunus affinis= Makino. =Prunus pseudocerasus jamasakura ×n incisa?= Makino. _Tokyo Bot. Mag._ =22=:99. 1908. Japan.

=45. Prunus sargentii= Rehder. _Mitt. Deutsch. Dendr. Ges._ =17=:159. 1908.

_Prunus puddum_ Miquel. _Ann. Mus. Lugd.-Bat._ =2=:90 (in part, not Wallich) 1865.

_Prunus pseudocerasus sachalinensis_ F. Schmidt. _Mém. Acad. Sci. St. Pétersburg sér._ 7, 12: No. 2. 124.

_Prunus pseudocerasus spontanea_ Maximowicz. _Bul. Acad. Sci. St. Pétersburg_ =29=:102.

_Prunus mume crasseglandulosa_ Miquel. Rijks-Herbarium, Leyden.

_Prunus pseudocerasus_ Sargent. _Garden and Forest_ =10=:462, fig. 58 (not Lindley) 1897.

_Prunus Sp. Zabel_. Beissner, Schelle & Zabel _Handb. Laubholz-Ben._ 241. 1903.

_Prunus pseudocerasus borealis_ Makino. _Tokyo Bot. Mag._ =22=:99. 1908.

_Prunus serrulata borealis_ Makino. _l. c._ =23=:75. 1909.

_Prunus pseudocerasus spontanea_ Koidzumi. _l. c._ 182.

_Prunus jamasakura elegans compta_ Koidzumi. _l. c._ =25=:186. 1911.

_Prunus jamasakura borealis_ Koidzumi. l. c. 187. Korea, Saghalin, Japan.

=46. Prunus tenuiflora= Koehne. _Plant Wils._ Pt. =2=:209. 1912. Western Hupeh.

=47. Prunus wildeniana= Koehne. _l. c._ 249. Hupeh.

=48. Prunus leveilleana= Koehne. _l. c._ 250. Korea.

=49. Prunus sontagiæ= Koehne. _l. c._ 250. Korea.

=50. Prunus mesadenia= Koehne. _l. c._ 250. Nippon.

=51. Prunus parvifolia= (Matsumura) Koehne. _l. c._ 251.

_Prunus pseudocerasus parvifolia_ Matsumura. _Tokyo Bot. Mag._ =15=:101. 1901.

_Prunus pseudocerasus typica parvifolia_ Koidzumi. _l. c._ =23=:182. 1909.

_Prunus jamasakura elegans parvifolia_ Koidzumi. _l. c._ =25=:186. 1911. Japan.

=Prunus parvifolia aomoriensis= Koehne. _Plant. Wils._ Pt. =2=:251. 1912. Northern Nippon.

=52. Prunus concinna= Koehne. _l. c._ 210. Western Hupeh.

=53. Prunus twymaniana= Koehne. _l. c._ 211. Western Szechuan.

Subsect. 9. CONRADINIA Koehne.

=54. Prunus conradinæ= Koehne. _Plant. Wils._ Pt. =2=:211. 1912. Western Hupeh.

=55. Prunus helenæ= Koehne. _l. c._ 212. Western Hupeh.

=56. Prunus saltuum= Koehne. _l. c._ 213. Western Hupeh.

=57. Prunus pauciflora= Bunge._ Mém. Étr. Acad. Sci. St. Pétersburg_ =2=:97 (_Enum. Pl. Chin. Bor._) 1835. Chili.

=58. Prunus sprengeri= Pampanini. _Nuov. Giorn. Bot. Ital_. =18=:230. 1911. Hupeh.

=59. Prunus yedoensis= Matsumura. _Tokyo Bot. Mag._ =15=:100. 1901. Cultivated in the gardens of Tokyo.

Subsect. 10. SERRULA Koehne.

=60. Prunus majestica= Koehne. _Plant. Wils._ Pt. =2=:252. 1912.

_Prunus puddum_ Franchet. _Pl. Delavay._ 197 (not Roxburgh following Brandis) 1889.

_Prunus cerasoides tibetica_ Schneider. Fedde _Rep. Nov. Sp._ =1=:54 (in part) 1905. Yunnan.

=61. Prunus serrula= Franchet. _Pl. Delavay_. 196. 1889. Yunnan.

=Prunus serrula tibetica= (Batalin) Koehne. _Plant. Wils._ Pt. =2=:213. 1912. Western Szechuan.

Subsect. 11. PUDDUM Koehne.

=62. Prunus campanulata= Maximowicz. _Bul. Acad. Sci. St. Pétersburg_ 29. 103.

_Prunus cerasoides_ Koidzumi. _Tokyo Bot. Mag._ =23=:181 (in part, not D. Don) 1909. Fokien.

Cultivated in Japan.

=63. Prunus hosseusii= Diels. Fedde _Rep. Nov. Sp._ =4=:289. 1907. Siam.

=64. Prunus cerasoides= D. Don. _Prodr. Fl. Nepal._ 239. 1825.

_Prunus silvatica_ Roxburgh. _Hort. Beng._ 92. 1814.

_Cerasus phoshia_ Hamilton. De Candolle _Prodr._ =2=:535. 1825.

_Cerasus puddum_ Seringe. De Candolle _Prodr._ =2=:537. 1825.

_Prunus puddum_ Roxburgh. _Forest Fl. Brit._ Ind. 194. 1874. Nepal.

=65. Prunus rufa= Steudel. _Nomencl_. Bot. =2=:404. 1841.

_Cerasus rufa_ Wallich. _Cat._ No. 721. 1829. Eastern Himalaya.

=66. Prunus trichantha= Koehne. _Plant. Wils._ Pt. =2=:254. 1912.

_Prunus rufa_ Hooker. _Fl. Brit. Ind._ =2=:314 (in part) 1878. Eastern Himalaya.

Subsect. 12. MICROCALYMMA Koehne.

=67. Prunus herincquiana= Lavallée. _Plant. Wils._ Pt. =2=:214. 1912. Western Hupeh.

=Prunus herincquiana biloba= (Franchet) Koehne. Western Hupeh.

_Prunus biloba_ Franchet in Herb. Paris. China.

=68. Prunus subhirtella= Miquel. _Ann. Mus. Lugd.-Bat._ =2=:91. 1865.

_Prunus subhirtella oblongifolia_ Miquel. _l. c._

_Prunus incisa_ Maximowicz. Bul. _Sci. Acad. St. Pétersburg_ =29=:99.

_Prunus pendula ascendens_ Makino. _Tokyo Bot. Mag._ =7=:103. 1893?

_Prunus herincquiana ascendens_ Schneider. _Ill. Handb. Laubholzk._ =1=:608. 1906.

_Prunus itosakra subhirtella_ Koidzumi. _Tokyo Bot. Mag._ =23=:180. 1908. Japan.

=Prunus subhirtella fukubana= Makino. _Tokyo Bot. Mag._ =22=:118. 1908.

_Prunus itosakra ascendens amabilis_ Koidzumi. _l. c._ =23=:181. 1909?

=69. Prunus pendula= Maximowicz. _Bul. Acad. Sci. St. Pétersburg_ =29=:98.

_Prunus itosakura_ Siebold. _Verh. Batav. Genoot._ 12: No. 1. 68. 1830.

_Cerasus pendula flore roseo_ Siebold. _Cat._ =5=:31. 1863, Maximowicz.

_Cerasus pendula rosea_ Dombrain. _Floral Mag._ 10. t. 536. 1871.

_Prunus subhirtella pendula_ Tanaka. _Useful Pl. Jap._ 153, fig. 620. 1895.

_Cerasus itosakura_ Siebold. Herb., Maximowicz. _l. c._

_Cerasus herincquiana_ Lavallée. _Icon. Arb. Segrez_, 117. 1885.

_Prunus miqueliana_ Schneider. _Ill. Handb. Laubholzk_, =1=:609 (not Maximowicz) 1906.

_Prunus herincquiana_ Schneider. _l. c._ 608.

_Cerasus pendula_ Siebold in herb., Koehne. _l. c._

_Prunus cerasus pendula flore roseo_ Koehne. _l. c._ (Horticultural)

_Prunus itosakra pendula_ Koidzumi. _Tokyo Bot. Mag._ =23=:180. 1909. Japan.

=70. Prunus taiwaniana= Hayata. _Jour. Coll. Sci. Tokyo_ =30=:87. 1911. Formosa.

=71. Prunus microlepis= Koehne. _Plant. Wils._ Pt. =2=:256. 1912. Hondo.

=Prunus microlepis ternata= Koehne. _l. c._ 256. Hondo.

Subsect. 13. CERASEIDOS (Siebold & Zuccarini) Koehne.

_Ceraseidos_ Siebold & Zuccarini. _Abh. Akad. Münch._ =3=:743 t. 5. 1843.

Ser. 1. PHYLLOPODIUM.

=72. Prunus setulosa= Batalin. _Act. Hort. Petrop._ =12=:165. 1892. Eastern Kansu.

=73. Prunus phyllopoda= Koehne. _Plant. Wils._ Pt. =2=:257. 1912. Northern Shensi.

=74. Prunus canescens= Bois. _l. c._ 215. Western Hupeh.

=75. Prunus veitchii= Koehne. _l. c._.257. Western Hupeh.

Ser. 2. DROSERINA.

=76. Prunus giraldiana= Schneider. _Fedde Rep. Nov. Sp._ =1=:65. 1905. Northern Shensi.

=77. Prunus droseracea= Koehne. _Plant. Wils._ Pt. =2=:215. 1912. Western Szechuan.

Ser. 3. OXYODON.

=78. Prunus trichostoma= Koehne. _l. c._ 216. Western Szechuan.

=79. Prunus latidentata= Koehne. _l. c._ 217. Western Szechuan.

=80. Prunus micromeloides= Koehne. _l. c._ 218. Western Szechuan.

=81. Prunus oxyodonta= Koehne. _l. c._ 218. Western Szechuan.

=82. Prunus glyptocarya= Koehne. _l. c._ 219. Western Szechuan.

=83. Prunus podadenia= Koehne. _l. c._ 258. Western China.

=84. Prunus lobulata= Koehne. _l. c._ 220. Western Szechuan.

=85. Prunus stipulacea= Maximowicz. _Bul. Acad. Sci. St. Pétersburg_ =11=:689. 1883. Kansu.

=86. Prunus pleuroptera= Koehne. _Plant. Wils._ Pt. =2=:221. 1912. Western Szechuan.

=87. Prunus zappeyana= Koehne. _l. c._ 221. Western Hupeh.

=Prunus zappeyana? subsimplex= Koehne. _l. c._ 222. Western Hupeh.

=88. Prunus incisa= Thunberg. _Fl. Jap._ 202. 1784.

_Cerasus incisa_ Loiseleur. _Nouveau Duhamel_ =5=:33. 1812.

_Ceraseidos apetala_ Miquel. _Ann. Mus. Lugd.-Bat._ =2=:93 1865 (in part). Japan.

Ser. 4. EUCERASEIDOS.

=89. Prunus caudata= Franchet. _Pl. Delavay._ 196. 1889. Yunnan.

=90. Prunus iwagiensis= Koehne. _Plant. Wils._ Pt. =2=:259. 1912. Hondo.

91. Prunus nipponica Matsumura. _Tokyo Bot. Mag_. =15=:99. 1901.

_Prunus miqueliana_ Koidzumi. _l. c._ =23=:184 (not Maximowicz) 1909.

_Prunus ceraseidos_ Maximowicz. _Bul. Acad. Sci. St. Pétersburg_ =29=:103.

_Prunus apetala typica_ Schneider. _Ill. Handb. Laubholzk._ =1=:608. 1906. Japan.

=92. Prunus autumnalis= Koehne. _Plant. Wils._ Pt. =2=:259. 1912.

_Prunus subhirtella autumnalis_ Makino. _Tokyo Bot. Mag._ =22=:117. 1908. Hondo.

=93. Prunus kurilensis= Miyabe. _Tokyo Bot. Mag._ =24=:11. 1910.

_Prunus ceraseidos kurilensis_ Miyabe. _Mem. Boston Soc. Nat. Hist._ =4=:226 (Fl. Kurile Isl.) 1890.

_Prunus incisa kurilensis_ Koidzumi. _Tokyo Bot. Mag._ =23=:184. 1909.

=94. Prunus nikkoensis= Koehne. _Plant. Wils._ Pt. =2=:260. 1912. Japan.

=95. Prunus miqueliana= Maximowicz. _Bul. Acad. Sci. St. Pétersburg_ =11=:692 (not Schneider) 1883. Japan.

=96. Prunus tschonoskii= Koehne. _Plant. Wils._ Pt. =2=:261. 1912.

_Prunus ceraseidos_ Maximowicz. _Bul. Acad. Sci. St. Pétersburg_ =29=:103.

_Prunus apetala iwozana_ Schneider. _Ill. Handb. Laubholzk._ =1=:608. 1906. Japan.

=97. Prunus apetala= (Siebold & Zuccarini) Franchet & Savatier. _Enum. Pl. Jap._ =2=:329. 1879 (not Zabel, cf. _P. maximowiczii_, No. 9).

_Ceraseidos apetala_ Siebold & Zuccarini. _Abh. Akad. Münch._ =3=:743. t. 5. 1843.

_Prunus ceraseidos_ Maximowicz. _Bul. Acad. Sci. St. Pétersburg_ =29=:103. Japan.

Ser. 5. AMBLYODON.

_98. Prunus gracilifolia_ Koehne. _Plant. Wils._ Pt. =2=:223. 1912. Western Hupeh.

=99. Prunus rossiana= Koehne. _l. c._ 223. Western Hupeh.

Div. II. MICROCERASUS (Spach, Roemer) Koehne.

_Cerasus_ sect. Microcerasus Spach. _Hist. Vég._ =1=:423. 1834.

_Microcerasus_ Webb. _Phytogr. Canar._ =2=:19. 1836-40.

Sect. 1. SPIRAEOPSIS Koehne.

Subsect. 1. MYRICOCERASUS Koehne.

=100. Prunus pumila= Linnaeus. _Mant. Pl._ 75. 1767. Eastern North America.

=101. Prunus besseyi= Bailey. _Bul. Cor. Ex. Sta._ =70=:261. 1894. Eastern North America.

Subsect. 2. SPIRAEOCERASUS Koehne.

=102. Prunus dictyoneura= Diels. _Bot. Jahrb._ 36, Beibl. 82, 57. 1905. Shensi.

=103. Prunus humilis= Bunge. _Mém. Étr. Acad. Sci. St. Pétersburg_ =2=:97 (_Enum. Pl. Chin. Bor._) 1833.

_Prunus salicina_ Lindley. _Trans. Hort. Soc. Lond._ =7=:239. 1830.

_Prunus bungei_ Walpers. _Rep._ =2=:9 (not Moris) 1893. China.

=104. Prunus glandulosa= Thunberg. _Fl. Jap._ 202. 1784.

_Amygdalus pumila_ Linnaeus. _Mant._ =1=:74. 1767.

_Cerasus glandulosa_ Loiseleur. _Nouv. Duhamel_ =5=:33. 1825.

=Prunus glandulosa glabra= Koehne. _Plant. Wils._ Pt. =2=:263. 1912.

_Prunus japonica glandulosa_ Maximowicz. _Bul. Soc. Nat. Mosc._ =54=:13. 1879. Japan.

=Prunus glandulosa glabra alba= Koehne. _Plant. Wils._ Pt. =2=:263. 1912.

_Prunus japonica_ Lindley. _Bot. Reg._ 8:t. 1801. 1835.

=Prunus glandulosa glabra rosea= Koehne. _Plant. Wils._ Pt. =2=:263. 1912.

_Prunus japonica typica flore roseo_ Maximowicz, in sched.

_Prunus japonica flor. simp._ Tanaka. _Useful Pl. Jap._ 153, fig. 621. 1895.

_Prunus japonica glandulosa_ Matsumura. _Tokyo Bot. Mag._ =14=:136. 1900. Japan.

=Prunus glandulosa glabra albiplena= Koehne. _Plant Wils._ Pt. =2=:264. 1912.

_Cerasus japonica multiplex_ Seringe. De Candolle _Prodr._ =2=:539 (in part) 1825.

_Prunus japonica flore pleno_ Siebold & Zuccarini. _Fl. Jap._ =1=:172 t. 90 f. 111. (in part) 1826.

_Prunus japonica_ Oudemans. _Neerlands Plantentuin_ t. 2. 1865.

_Prunus japonica flore albo pleno_ Lemaire. _Ill. Hort._ 5: t. 183. 1858.

_Prunus japonica_ Maximowicz. _Bul. Soc. Nat. Mosc._ 54. 14 (in part) 1879.

_Prunus japonica multiplex_ Makino. _Tokyo Bot. Mag._ =22=:72 (in part) 1908. Japan.

=Prunus glandulosa purdomii= Koehne. _Plant. Wils._ Pt. =2=:264. 1912. Northern China.

=Prunus glandulosa trichostyla= Koehne. _l. c._ 224.

=Prunus glandulosa trichostyla faberi= Koehne. _l. c._ 224.

_Prunus japonica_ J. Hutchinson. _Bot. Mag._ 135: t. 8260 (not Thunberg) 1909. Shantung.

=Prunus glandulosa trichostyla paokangensis= (Schneider) Koehne. _Plant. Wils._ Pt. =2=:264. 1912.

_Prunus japonica packangensis_ Schneider. _Fedde Rep. Nov. Sp._ =1=:53. 1905. Western Hupeh.

=Prunus glandulosa trichostyla sinensis= (Persoon) Koehne. _Plant. Wils._ Pt. =2=:265. 1912.

_Amygdalus indica nana_ Plukenett. _Phytogr._ 1: t. 11. f. 4 (1691, new edit. 1769).

_Prunus sinensis_ Persoon. _Syn._ =2=:36. 1807.

_Cerasus japonica_ Seringe. De Candolle _Prodr._ =2=:539 (in part) 1825.

_Prunus japonica flore pleno_ Siebold & Zuccarini. _Fl. Jap._ =1=:172 t. 90 f. 111. (in part) 1826.

_Prunus japonica_ Maximowicz. _Bul. Soc. Nat. Mosc._ =54=:14 (in part) 1883. Northern Shensi.

=Prunus glandulosa salicifoli= (Komarov) Koehne. _Plant. Wils._ Pt. =2=:265. 1912.

_Prunus japonica salicifolia_ Komarov. _Act. Hort. Petrop._ =22=:754. 1904. Shing-king.

=105. Prunus pogonostyla= Maximowicz. _Bul. Soc. Nat. Mosc._ =54=:11. 1879.

_Prunus formosana_ Matsumura. _Tokyo Bot. Mag._ =15=:86. 1901.

=Prunus pogonostyla globosa= Koehne. _Plant. Wils._ Pt. =2=:265. 1912. Formosa.

=Prunus pogonostyla obovata= Koehne. _l. c._ 265. Formosa.

=106. Prunus japonica= Thunberg. _Fl. Jap._ 201. 1784.

_Prunus japonica japonica_ Maximowicz. _Bul. Soc. Nat. Mosc._ =54=:12. 1879.

_Prunus japonica typica_ Matsumura. _Tokyo Bot. Mag._ =14=:135. 1900.

=Prunus japonica eujaponica= Koehne. _Plant. Wils._ Pt. =2=:266. 1912.

=Prunus japonica eujaponica fauriei= Koehne. _l. c._ 266. Japan.

=Prunus japonica eujaponica oldhamii= Koehne. _l. c._ 266. Hupeh.

=Prunus japonica gracillima= Koehne. _l. c._ 266.

=Prunus japonica gracillima thunbergii= Koehne. _l. c._ 266.

_Prunus japonica thunbergii_ Koehne. Fedde _Rep. Nov. Sp._ =8=:23. 1910. Cultivated in the Späth Arboretum near Berlin, received from St. Petersburg.

=Prunus japonica gracillima engleri= Koehne. _Plant. Wils._ Pt. =2=:266. 1912.

_Prunus japonica engleri_ Koehne. _l. c._ 266. Manchuria.

=Prunus japonica gracillima minor= Koehne. _l. c._ 267. Cultivated in the Späth Arboretum, Berlin.

=Prunus japonica gracillima sphaerica= (Carrière) Koehne. _l. c._ 267.

_Prunus japonica sphaerica_ Carrière. _Rev. Hort._ 468, fig. 163. 1890.

=Prunus japonica kerii= (Steudel) Koehne. _Plant. Wils._ =Pt. 2=:267. 1912.

_Prunus japonica_ Ker-Gawler. _Bot. Reg._= 1=: t. 27. 1815.

_Amygdalus pumila_ Sims. _Bot. Mag._ =47=: t. 2176. 1820.

_Prunus kerii_ Steudel. _Nomencl. Bot._ ed. 2, 403. 1841, which cites "_Cerasus" japonica_ Ker-Gawler.

_Prunus japonica typica flore pleno_ Zabel. Beissner, Schelle & Zabel _Handb. Laubholz-Ben._ 238. 1903. Chekiang. Cultivated in England.

? =Prunus praecox= Carrière. _Rev. Hort._ 488, fig. 142, 143. 1892. Originated from sowings of _Prunus japonica sphaerica_ and supposed to be _Prunus japonica_ × _domestica._

=107. Prunus nakaii= Léveillé. Fedde _Rep. Nov. Sp._ =7=:198. 1909. Korea.

=108. Prunus carcharias= Koehne. _Plant. Wils._ Pt. =2=:267. 1912. Szechuan.

Sect. 2. =AMYGDALOCERASUS= Koehne.

_Cerasus_ sect. _Microcerasus_ Spach.

_Microcerasus_ Webb. _Phytogr. Canar._ =2=:19 (1836-50); Schneider _Ill. Handb. Laubholzk._ =1=:601. 1906.

_Prunus_ subgen. _Microcerasus_ Focke. Engler & Prantl _Natürl. Pflanzenfam._ =3=:3, 54. 1888.

_Prunus_ sect. _Trichocerasus_ et subgen. _Microcerasus_ Koehne. _Deutsche Dendr._ 302, 306. 1893.

=109. Prunus tomentosa= Thunberg. _Fl. Jap._ 203. 1784.--Siebold & Zuccarini _Fl. Jap._ =1=:51, t. 22. 1826. Japan, western and northern China.

=Prunus tomentosa spaethiana= Koehne. _Plant. Wils._ =Pt. 2=:269. 1912. Cultivated in European gardens.

=Prunus tomentosa graebneriana= Koehne. _l. c._ 269. Cultivated near the Botanic Garden, Berlin-Dahlem.

=Prunus tomentosa insularis= Koehne. _l. c._ 269. Japan. Cultivated in Japan.

=Prunus tomentosa souliei= Koehne. _l. c._ 269. Szechuan.

=Prunus tomentosa kashkarovii= Koehne. _l. c._ 269. Tibet.

=Prunus tomentosa endotricha= Koehne. _l. c._ 225. Western Hupeh.

=Prunus tomentosa breviflora= Koehne. _l. c._ 270. Northern Shensi.

=Prunus tomentosa trichocarpa= (Bunge) Koehne. _Plant. Wils._ =Pt. 2=:270. 1912.

_Prunus trichocarpa_ Bunge. _Mém. Étr. Acad. Sci. St. Pétersburg_ =2=:96 (_Enum. Pl. Chin. Bor._) 1833. Northern China.

=Prunus tomentosa tsuluensis Koehne.= _Plant. Wils._ Pt. =2=:270. 1912. Northern Shensi.

=Prunus tomentosa heteromera Koehne.= _l. c._ 270. Szechuan.

=110. Prunus batalinii= (Schneider) Koehne. _l. c._ 270.

_Prunus tomentosa_, (?) _Batalinii_ Schneider. Fedde _Rep. Nov. Sp._ =1=:52. 1905. Szechuan.

=111. Prunus cinerascens= Franchet. _Nouv. Arch. Mus. Paris._ sér. 2, =8=:216 (_Pl. David._ II. 34) 1885. Western Szechuan.

=112. Prunus jacquemontii= (Edgeworth) Hooke. _Fl. Brit. Ind._ =2=:314. 1878. Afghanistan, Northwestern Himalaya, Tibet.

=113. Prunus incana= (Pallas) Steven. _Mém. Soc. Nat. Mosc._ =3=:263. 1812. Armenia, Georgia, Himalaya? Cf. =Cerasus hippophaeoides= Bornmüller. _Oester. Bot. Zeit._ =49=:15. 1899. Cappadocia.

=114. Prunus griffithii= (Boissier) Schneider. _Ill. Handb. Laubholzk._ =1=:606. 1906. Afghanistan.

=115. Prunus prostrata= Labillardière. _Icon. Pl. Syr._ =1=:15, t. 6. 1791. Southern Europe, Crete, Algier, Western Asia to Persia and Syria. Cf. =Prunus bifrons= Fritsch. _Sitz. Akad. Wien_ =101=: pt. 1. 636, t. 3, fig. 1. 1892. Himalaya?

=116. Prunus brachypetala= (Boissier) Walpers. _Ann._ =1=:272. 1848-49. Southern Persia.

=117. Prunus microcarpa= C. A. Meyer. _Verz. Pfl. Caucas. Casp._ 166. 1831. Caucasia, Northern Persia. Cf. =Cerasus tortuosa= Boissier & Haussknecht. Boissier _Fl. Or._ =2=:647. 1872. Antilibanon, Cappadocia, Kurdistan.

=118. Prunus verrucosa= Franchet. _Ann. Sci. Nat. sér._ 6, =16=:280. 1883. Turkestan. Cf. =Prunus calycosus= Aitchison & Hemsley. _Trans. Linn. Soc._ =3=:61, t. 8. 1888. Afghanistan.

=119. Prunus diffusa= (Boissier & Haussknecht) Schneider. _Ill. Handb. Laubholzk._ =1=:606. 1906. Southwestern Persia.

The geographical distribution of these cherries is most interesting.[5] From North America come but five species of cherries but two of which, _Prunus besseyi_ and _Prunus pumila_, furnish food and these two as yet are but sparingly grown; all five, however, are more or less used as stocks.

Greene[6] has described, in addition to the five accepted ones, eleven new species of true cherries from the far west of the type of _Prunus emarginata_, some of which at least have furnished food to the Indians, miners and trappers and may have horticultural possibilities for the desert regions in which they are found either for fruit or as stocks.

From the western portion of the Old World, including all of Europe, northern Africa, Asia Minor, Persia, Turkestan and Afghanistan come 14 species. From this region, though the number of species as compared with East Asia is small, we have all of the cultivated esculent cherries, if possibly _Prunus tomentosa_ be excepted. Though nearly all of the species of this large territory are found--possibly all originated there--in the southeastern part of Europe and the adjoining southwestern part of Asia, yet they seem, with one or two exceptions, to be quite distinct from the species of the eastern half of the Old World--the Himalaya Mountains separating the two regions. It is probable that when west central Asia has been as well explored botanically as the east central part of the continent, many new species will be added to Prunus and its sub-genus Cerasus.

It is in the eastern half of the Old World that the cherry flora is richest. More than 100 of the 119 species of Cerasus recognized by Koehne are found in the Himalaya Mountains and the region to the east including Japan and the Kuril Islands. Yet out of all of this wealth of raw material only _Prunus tomentosa_ has been truly domesticated as an esculent though possibly a score of these species are well-known ornamentals. Of the 100 eastern Asiatic species about 75 belong to China--the remainder to Formosa, Siam and Japan with its islands. Happily these Chinese cherries are being introduced, but a few at a time, it is true, to Europe and America and it can hardly be otherwise than that they will enrich horticulture as they are domesticated, hybridized or used as a consort upon which to grow the cherries now known to cultivation. In particular, it may be expected that cherries for the cold north and the bleak plains of our continent will be evolved from the Asiatic species better suited to these regions than the cultivated cherries we now grow.

The number and diversity of the species of cherries which this brief review of Cerasus shows to exist suggest that our cultivated cherry flora is but begun. There can be no question but that others of these species than the few that have been domesticated will yield to improvement under cultivation and furnish refreshing fruits. It is just as certain that new types, as valuable perhaps as the hybrid Dukes we now have, can be produced through hybridization. In North America, we have no satisfactory stock for cultivated Sweet and Sour Cherries. Both of the stocks now commonly used, the Mazzard and the Mahaleb, as we shall see, have weaknesses that unfit them for general use. Surely out of the great number of forms we have just listed a better stock than either of the two named can be found. No doubt, too, many of these new species, even though they do not furnish food, will prove valuable timber or ornamental trees.

We are ready now for a more detailed discussion of the cultivated species of cherries.

[3] The leaves are conduplicate in vernation in a few species of American plums; these species are intermediate between plums and cherries.

[4] The species are given as classified by Koehne, _Plantae Wilsonianae_ Pt. =2=:237-271. 1912. The liberty has been taken of changing the form of Koehne's citations to conform to that used at this Station. For the sake of brevity some of the citations of the original author have been omitted. Space does not permit the publication of Koehne's system of classification. This may be found in _Plantae Wilsonianae_ Pt. =2=:226-237. 1912.

Conservative botanists will hardly accept all of Koehne's species, in describing which the author tells us he labored under the difficulty of paucity of material and that as more material comes to hand there must, therefore, be revisions. These species are provisionally accepted in _The Cherries of New York_ under the belief that botany and horticulture are best served by giving names freely so that all forms to which reference may need to be made may thus be better identified.

The botanical student of Cerasus is referred to Schneider's comprehensive discussion of Prunus in his _Handbuch der Laubholzkunde_ =1=:589-637. 1906 and =2=:973-993; also Koehne's monographs of Cerasus, Sargent, C. S., _Plantae Wilsonianae_ Pt. =2=:197-271. 1912. Profitable though it might be, space does not permit in _The Cherries of New York_ a botanical discussion of other than the species cultivated for their fruits.

[5] Koehne has presented the results of a careful study of the distribution of cherries in _Mitt. Deutsch. Dendr. Ges._ 168-183. 1912.

[6] Greene (_Proc. Biol. Soc. Wash._ =18=:55-60. 1905), preferring Cerasus to Prunus as a generic name for racemose cherries, gives the following new species: _Cerasus californica_ (_Fl. Francis_. 50. 1891) from the hills of middle western California; _Cerasus crenulata_ from the Mongolian Mountains, New Mexico; _Cerasus arida_ inhabiting the borders of the desert at the eastern base of the San Bernardino Mountain, California; _Cerasus prunifolia_ found in the mountains of Fresno County, California; _Cerasus rhamnoides_ collected at Mud Springs, Amador County, California; _Cerasus kelloggiana_ from the middle Sierra Nevada Mountains in California; _Cerasus padifolia_ collected in the foothills near Carson City, Nevada; _Cerasus obliqua_ described from a single specimen from Oroville, California; _Cerasus parviflora_ known only from Mt. Shasta, California; _Cerasus obtusa_ from the arid interior of southeastern Oregon; and _Cerasus trichopetala_ found at Columbia Falls, Montana. The type specimens of these eleven species are in the National Herbarium at Washington.

PRUNUS CERASUS Linnaeus.

I. Linnaeus _Spec. Pl._ 474. 1753.

_P. austera._ 2. Ehrhart _Beitr._ =5=:160. 1790.

_P. acida._ 3. Ehrhart _l. c._ 1790.

_P. aestiva._ 4. Salisbury _Prodr._ 356. 1796.

_P. plena._ 5. Poiret, in Lamarck _Enc. Méth. Bot._ =5=:671. 1804.

_P. rosea._ 6. Poiret, in Lamarck _l. c._ 1804.

_P. Juliana._ 7. Reichenbach _Fl. Germ. Exc._ 643. 1832, not Poiret in Lamarck, 1805.

_P. hortensis._ 8. Persoon _Syn. Pl._ =2=:34. 1807.

_P. Marasca._ 9. Reichenbach _Fl. Germ. Exc._ 644. 1832.

_P. oxycarpa._ 10. Bechstein _Forst. Bot._ =5=:424. 1843.

_P. vulgaris._ 11. Schur _Enum. Pl. Transsilv._ 954. 1866.

_Cerasus vulgaris._ 12. Miller _Gard. Dict._ ed. 8:No. 1. 1768.

_C. hortenses._ 13. Miller _l. c._ No. 3. 1768.

_C. acida._ 14. Borkhausen, in Roemer _Arch. Bot._ =1=:11, 38. 1796.

_C. austera._ 15. Borkhausen, in Roemer _l. c._ 1796.

_C. Caproniana._ 16. De Candolle _Fl. Fran._ ed. 3, =4=:842. 1805.

_C. nicotianaefolia._ 17. Hort. ex De Candolle _Prodr._ =2=:536. 1825.

_C. bigarella._ 18. Dumortier _Fl. Belg._ 91. 1827.

_C. effusa._ 19. Host _Fl. Austr._ =2=:6. 1831.

_C. Marasca._ 20. Host _l. c._ 1831.

_C. Bungei._ 21. Walpers _Rep._ =2=:9. 1843.

_C. Heaumiana._ 22. Roemer _Syn. Rosifl._ 69. 1847.

_C. tridentina._ 23. Roemer _l. c._ 76. 1847.

_C. Rhexii._ 24. Hort. Gall. ex Van Houtte _Fl. Serres, sér._ 2, =7=:159. 1868.

_C. cucullata._ 25. Hort. ex Koch _Dendrol._ =1=:6. 1869.

Tree low, reaching a height of twenty to thirty feet, diffuse, open-headed, round-topped or spreading, often without a central leader; trunk at maturity a foot in diameter; bark reddish-brown overlaid with ashy-gray, smooth or sometimes roughened; branches spreading, slender and more or less drooping; branchlets slender and willowy, glabrous, reddish-brown becoming darker and overspread with ashy-gray; lenticels small, numerous, conspicuous, raised.

Leaves resinous at opening, more or less erect, very numerous, three to four inches long and from one-half to two inches wide, obovate to oval, folded upward, thick and firm in texture; upper surface dark green, smooth, the lower surface paler green, with more or less pubescence; apex taper-pointed or acute, base abrupt or acute; margins finely serrate, often doubly so, teeth tipped with small, dark glands; petioles from a half-inch to two inches long, slender, grooved, with a few hairs on the upper surface, tinged with red; glands from one to four, usually small, variously colored, globose or reniform, usually at the base of the blade; stipules small, lanceolate, narrow, finely serrate, early caducous.

Winter-buds small, short, obtuse or pointed, plump and free, arranged singly or in clusters; leaf-scars usually prominent; flowers appearing with or after the leaves, showy, an inch across, white; borne in dense or scattered, very scaly clusters and in twos, threes and fours on one-year-old wood; pedicels from a half to an inch and a half in length, slender, green and glabrous; calyx-tube obconic, glabrous, green or tinged with red; calyx-lobes broadly obtuse or acute, glabrous on both surfaces, reflexed, margin serrate, faintly red; petals white, roundish or oval to obovate, entire or crenate, sessile or nearly so; stamens about thirty, filaments one-fourth of an inch in length; anthers yellow; pistils about as long as the stamens, glabrous.

Fruit roundish-oblate or cordate, sides slightly compressed, about three-fourths of an inch in diameter; suture lacking or indistinct; cavity well marked, usually abrupt; apex usually depressed; color from light to dark red; dots numerous, small, russet, more or less conspicuous; stem slender, from a half-inch to two inches in length, glabrous, without bloom; skin usually separating readily from the pulp; flesh dark red, with dark colored juice or pale yellow with colorless juice, tender, melting, sprightly, more or less acidulous, sometimes astringent; stone free or more or less clinging, roundish, pointed or blunt, smooth, less than a half inch in diameter; ventral suture usually ridged, sometimes smooth.

The numerous synonyms of _Prunus cerasus_ indicate the state of confusion which prevails in the scientific nomenclature of the Sour Cherry. Yet the names given are scarcely a tithe of those that have been discarded or superseded for a whole or a part of this species by botanists. Happily, there is no language in which there is a possibility of confusing the Sour Cherry with the other two or three species of cultivated cherries if the common names be used. That men, learned or unlearned, speaking in their mother tongues distinguish species of cherries so readily by their common names, is ample excuse for not attempting to give in a pomological work all of the Latin names of the Sour Cherry that have been used by the many men who have at one time or another attempted to classify the plants in Prunus. Those here published are from botanists who have contributed most to the knowledge of the species.

_Prunus cerasus_ is the Sour Cherry, or Pie Cherry, of many languages--grown and esteemed in temperate climates the world over and probably the most widely distributed of all tree fruits. The species is found truly wild, as we have set forth in detail in the following chapter, in southwestern Asia and southeastern Europe. It is a frequent escape from cultivation, multiplying from seed distributed by birds or human agencies or growing from suckers which spring so freely from the roots as to make the species unfit for a stock in orchard work. The number of cultivated varieties of _Prunus cerasus_ listed in _The Cherries of New York_ is 270. Sour Cherries cultivated for their fruits constitute two distinct groups, each of which is again divided into many varieties. The two groups vary more or less in both tree and fruit but have a constant difference only in a single, very easily distinguished character--the juice in the fruits of one is red, in the other it is colorless.

The cherries with colorless juice are the Amarelles, from the Latin for bitter, a term probably first used by the Germans but now in general use wherever these cherries are grown, though the English often designate them as Kentish cherries and the French as Cerisier Commun. These Amarelles are pale red fruits, more or less flattened at the ends. Despite the derivation of the name Amarelle, they have less bitterness than the other group of varieties of the Sour Cherry. They are also less acid than the darker colored cherries and are therefore more suitable for eating out of hand while the dark colored cherries are almost exclusively culinary fruits. The common representatives of this group are Early Richmond, Montmorency and the various cherries to which the word Amarelle is affixed, as the King Amarelle and the Späte Amarelle.

The second group, varieties with reddish juice and usually with very dark fruits which are more spherical or cordate in shape than the Amarelles, comprises the Morellos of several languages or the Griottes of [Illustration: _PRUNUS CERASUS_ (MORELLO GROUP)] the French. The first of these terms has reference to the color, the word Morello coming from the Italian meaning blackish while Griotte, from the French, probably is derived through agriotte from aigre, meaning sharp, in reference to the acidity of these cherries. Weichsel is the German group name for these cherries, rather less commonly used than the other two terms. The trees of the Morello-like varieties are usually smaller, bushier and more compact than those of the Amarelles. The branches, as a rule, are more horizontal, often drooping, are less regularly arranged and are more slender. The leaves, in typical varieties, are smaller, thinner, a darker green and are pendant while those of the Amarelles are either inclined to be upright or horizontal; the leaves are also toothed less deeply and more regularly. These differences in the leaves are well shown in the color-plates of the varieties of the two groups. There are differences, also, in the inflorescence and the floral organs in the extreme types but these disappear in the varieties that connect the two forms. The typical varieties of this group are English Morello, Ostheim, Olivet, Brusseler Braune, Vladimir and Riga.

Attempts to give precise distinctions between the fruits and trees of the two groups fail because the varieties constituting them hybridize freely making it impossible, with the more or less blended characters, to classify accurately. The group name indicates but little more than whether the cherries have a colored or a colorless juice--a distinction well worth while for the fruit-grower.

Ehrhart called Sour Cherries with colorless juice _Prunus acida_ and those with dark colored juice _Prunus austera_. To some extent botanists have followed Ehrhart's designations. Linnaeus thought the two groups sufficiently distinct to be botanical varieties of the species and denominated the cherry with colorless juice _Prunus cerasus caproniana_ and the one with colored juice _Prunus cerasus austera_.

A third division of the species is the Marasca cherry from which is made maraschino, a distilled liqueur much used in Europe as a drink and in Europe and America in the manufacture of maraschino cherries. The Marasca cherry is a native of the province of Dalmatia, Austria, where the trees grow wild and are now sparingly cultivated. In 1831 Host gave this form the name _Cerasus marasca_ and a year later Reichenbach described it as _Prunus marasca_. Botanists now very generally include it in the species under discussion and Schneider[7] makes it a botanical variety, _Prunus cerasus marasca_, a disposition which we believe to be the best. The Marasca cherries differ from the other cultivated forms chiefly in the greater vigor of the trees, relatively finer serrations of the leaves, longer stipules and a more compact inflorescence. The fruits are much smaller than in the common Sour Cherries, are deep red or almost black in color and have intensely red flesh and juice. The cherries are very acid with a bitter taste that gives flavor to the maraschino made from them.

Besides these divisions of the species cultivated for their fruits botanists describe several botanical forms which either have no horticultural value or are cultivated exclusively as ornamentals. It is not necessary to discuss these in a pomological work. Of these botanical derivatives of _Prunus cerasus_, Schneider enumerates nine and three hybrids between this and other species.[8]

[7] Schneider, C. K. _Handb. Laubh_. =1=:615. 1906.

[8] Schneider, C. K. _Handb. Laubh._ =1=:1906; =2=:1912.

PRUNUS AVIUM Linnaeus.

1. Linnaeus _Fl. Suec._ ed. =2=:165. 1755.

_P. nigricans_. 2. Ehrhart _Beitr._ =7=:126. 1792.

_P. varia_. 3. Ehrhart _l. c._ 127. 1792.

_P. sylvestris_. 4. Persoon _Syn. Pl._ =2=:35. 1807.

_P. dulcis_. 5. Miller ex Reichenbach _Fl. Germ. Exc._ 644. 1832.

_Cerasus nigra_. 6. Miller _Gard. Dict._ ed. 8: No. 2. 1768.

_C. Avium_. 7. Moench _Méth._ 672. 1794.

_C. varia_. 8. Borkhausen, in Roemer _Arch._ 1., =2=:38. 1796.

_C. Juliana_. 9. De Candolle _Fl. Fran._ =4=:483. 1805.

_C. duracina_. 10. De Candolle _l. c._ 1805.

_C. rubicunda_. 11. Bechstein _Forstb._ 160, 335. 1810.

_C. intermedia_. 12. Host _Fl. Austr._ =2=:7. 1831, not Loisel. in Duham. 1812.

_C. decumana_. 13. Delaunay ex Seringe, in De Candolle _Prodr._ =2=:536. 1825.

_C. macrophylla_. 14. Sweet Hort. _Brit. ed._ =1=:485. 1827.

_C. dulcis_. 15. Borkhausen ex Steudel _Nom. Bot._ ed. sec., =1=:331. 1840.

_C. pallida_. 16. Roemer _Syn. Rosifl._ 69. 1847.

_C. heterophylla_. 17. Hort. ex Koch _Dendrol._ =1=:106. 1869.

_C. asplenifolia_. 18. Hort. ex Koch _l. c._ 1869.

_C. salicifolia_. 19. Hort. ex Koch _l. c._ 1869, not Ser. in De Candolle. 1825.

Tree reaching a height of thirty to forty feet, vigorous, upright-spreading, open-topped, semi-hardy, usually with a central leader; trunk a foot or more in diameter roughened; branches rather stocky, smooth, dull ash-gray, with few small lenticels; branchlets thick, long, with long internodes, grayish-brown, smooth, with small, inconspicuous lenticels.

Leaves resinous at opening, more or less drooping, numerous, four to six inches long, two to three inches wide, strongly conduplicate, oblong-ovate, thin; upper surface dark green, rugose or sometimes smooth; lower surface dull green, more or less pubescent; apex acute, base more or less abrupt; margin coarsely and doubly serrate, glandular; petiole one and three-fourths inches long, slender, dull red, with from one to three small, globose, reddish glands on the stalk; stipules small, lanceolate, finely serrate, early caducous.

Buds rather small, of medium length, pointed, appressed or free, arranged singly or in small, scaly clusters at the tips of branchlets or on short spurs; leaf-scars prominent; blooming with or after the leaves; flowers white, one and one-quarter inches across; in clusters of two or three; pedicels one inch long, slender, glabrous; calyx-tube green or with a faint red tinge, brownish-yellow within, campanulate; calyx-lobes faintly tinged with red, long, acute, margin serrate, glabrous within and without, reflexed; petals oval, entire or crenate, tapering to a short, blunt claw; stamens nearly one-half inch long, thirty-five or thirty-six; anthers yellow; pistil glabrous, shorter than the stamens.

Fruit ripening in early July; about an inch in diameter, cordate; cavity deep, wide, abrupt; suture a line; apex roundish or pointed; color ranging from yellow through red to purplish-black; dots numerous, small, russet, inconspicuous; stem tinged with red, one and one-half inches long, adherent to the fruit; skin toughish, adherent to the pulp; flesh yellow, red, or dark purple with colorless or colored juice, tender to firm, sweet; stone semi-clinging, three-eighths of an inch long, not as wide as long, elliptical, flattened, blunt, with smooth surfaces.

Through its cultivated varieties _Prunus avium_ is everywhere known in temperate climates as the Sweet Cherry. In the wild state it is variously called Mazzard, Bird, Wild, Crab and the Gean cherry. It is not as hardy a species as _Prunus cerasus_ and is, therefore, less generally grown but still is a favorite orchard, dooryard and roadside plant in all mid-temperate regions. It refuses to grow, however, in the warmest and coldest parts of the temperate zones. Wherever the species thrives as an orchard plant it is to be found growing spontaneously along fences and roadsides and in open woods from seeds distributed by birds. The fruits of these wild Sweet Cherries are usually small and the flesh thin and dry, often unpalatable; but, on the other hand, trees are sometimes found as escapes from cultivation which rival in their products the orchard-grown cherries. It is from reverted seedlings that the description of the species herewith given has been made. The number of cultivated varieties of _Prunus avium_ listed in _The Cherries of New York_ is 549.

The habitat of the species and its history as a cultivated plant are given in the following chapter. A further point of horticultural interest as regards its habitat is that wherever found truly wild, as in its original home in southern and central Europe and Asia Minor, it is to be found in moderately dry, calcareous soils and seldom in the shade, preferring always warm, sunny sites, as gravelly or stony hillsides. These predilections cling to the species in its cultivated varieties. _Prunus avium_ differs from _Prunus cerasus_ in an important horticultural character as the two species grow spontaneously--the former suckers from the root little or not at all, making it a suitable plant for a stock in orchard work, while the latter suckers so much as to make it unfit for use as a stock.

_Prunus avium_ is variously divided by botanists and pomologists. Whatever distinct forms of the species may exist in the wild state, they are now interminably confused by hybridization under cultivation. It is impossible to divide the species into botanical varieties from the characters of the horticultural varieties, as many botanists have attempted to do. The species can be roughly divided into two pomological groups, the distinguishing character being the texture of the flesh.

Sweet Cherries with soft, tender flesh form one group known by pomologists under the French group name Guigne or the English Gean. These are also the Heart cherries of common parlance. These soft-fruited cherries may again be divided into dark colored varieties with reddish juice and light colored sorts with colorless juice. Typical light colored Geans are Coe, Ida, Elton and Waterloo; dark colored ones are Black Tartarian, Early Purple and Eagle. It is to this group of cherries that Linnaeus gave the varietal name _Juliana_ and De Candolle the specific name _Cerasus Juliana_.

The second group is distinguished by the firm, breaking flesh of the fruits--the Bigarreaus of several languages, the name originally having reference to the diverse colors of the fruits. This group is further divisible in accordance with color of fruit and juice into black Bigarreaus and light Bigarreaus. Chief of the black cherries falling into this division are Windsor, Schmidt and Mezel; of the light ones, which are much more numerous, Yellow Spanish and Napoleon are representative sorts. Linnaeus called these hard-fleshed cherries _Prunus avium duracina_; De Candolle called them _Cerasus duracina_; K. Koch, _Prunus avium decumana_; and Roemer, _Cerasus bigarella_.

Besides these two orchard forms of _Prunus avium_ several other horticultural forms, quite as distinct or even more so, are grown as ornamentals, some of which are listed as distinct species or as botanical varieties of _Prunus avium_. To add to the confusion, a number of Latinized garden names are more or less commonly applied to these ornamental Sweet Cherries. Schneider,[9] in revising the genus Prunus, names four botanical forms of _Prunus avium_ and two natural hybrids with other species.

[9] Schneider, C. K. _Handb. Laubh._ =1=:1906; =2=:1912.

PRUNUS AVIUM × PRUNUS CERASUS

The Duke cherries, long placed by most pomologists and botanists in a botanical variety of _Prunus avium_, are unquestionably hybrids between the Sweet Cherry and the Sour Cherry. A study of the characters of the varieties of the Duke cherries shows all gradations between _Prunus cerasus_ and _Prunus avium_, though, in the main, they resemble the latter more than the former, differing from the Sweet Cherries most noticeably in having an acid flesh. Sterility is a common attribute of hybridism. In this respect the Dukes behave like most hybrids. In several Duke cherries all of the seeds collected at this Station are sterile; in others, most of them are sterile and in none are the seeds as fertile as in varieties known to be pure bred as to species. So, too, shrunken pollen grains indicate hybridity. A study of the pollen of the Duke cherries shows many grains, the greater proportion, to be abnormal, a condition not found in the pollen of varieties true to species. May Duke, Reine Hortense and Late Duke are the leading hybrid varieties.

There are dark colored Duke cherries with reddish juice and light colored sorts with uncolored juice, just as in the two parent species. May Duke is a typical variety with colored juice while Reine Hortense is probably the best-known cherry among these hybrids with uncolored juice. About 65 of the cherries listed in _The Cherries of New York_ are "Dukes," or hybrids between the Sweet and the Sour Cherry.

The name Duke comes from the variety May Duke which is a corruption of Médoc, a district in the department of Geronde, France, from whence this variety came. The cherries of this group are known as Dukes only in England; in France the name Royale is similarly used.

These hybrid cherries have been placed in a distinct botanical group by several botanists. They constitute the _Cerasus regalis_ Poiteau and Turpin (_Traite des Arb. Fruit_. 123); the _Cerasus bigarella regalis_ Roemer (_Syn. Monogr_. =3=:69); and the _Prunus avium regalis_ Bailey (Cyc. _Am. Hort_. 1453. 1901).

PRUNUS MAHALEB Linnaeus.

1. Linnaeus _Sp. Pl._ 474. 1753. 2. Bailey _Cyc. Am. Hort._ =3=:1451. 1901. 3. Schneider _Handb. Laubh._ =1=:617. 1906.

_Cerasus mahaleb._ 4. Miller _Gard. Dict._ ed. 8: No. 4. 1759.

_Padus mahaleb._ 5. Borkhausen _Handb. Forstb._ =2=:1434. 1803.

Tree small, slender, vigorous, upright-spreading, open-topped; branches roughened, ash-gray over reddish-brown; branchlets numerous, slender and firm-wooded, with short internodes, dull gray, glabrous, with very numerous large, raised lenticels.

Leaves numerous, an inch in length, one and one-fourth inches wide, ovate to obovate, thick, leathery; upper surface dark green, glossy, smooth; lower surface light green, slightly pubescent along the midrib; apex and base abrupt; margin finely crenate, with reddish-brown glands; petiole one-half inch long, slender, greenish, with none or with from one to three small, globose, greenish glands variable in position.

Buds small, short, obtuse, appressed or free, arranged singly as lateral buds and in clusters on small, slender spurs; flowers appearing late, after the leaves, small, averaging one-half inch across, white, fragrant; borne in clusters of six to eight scattered on a main stem an inch in length, with the terminal pedicels one-quarter inch long and basal pedicels one-half inch long; pedicels slender, glabrous, greenish; calyx-tube green, campanulate, glabrous; calyx-lobes narrow, entire, glabrous, reflexed; petals white, small, separated, ovate, tapering to short, narrow claws; filaments one-fourth inch long; pistil glabrous, about equal to the stamens in length.

Fruit matures about the middle of July; very small, one-fourth inch long, one-third inch wide, roundish-ovate; cavity shallow and abrupt; suture shallow or a mere line; apex roundish to slightly pointed, with stigma usually adherent; color black; stem slender, length of corymb about one and one-half inches; length of fruit-stem about one-quarter inch; skin thick, tough; flesh reddish-black, with scant reddish-black juice, tender and soft, very astringent, sour, not edible; stone free or nearly so, very small, averaging nine thirty-seconds inch long and seven thirty-seconds inch wide, ovate, slightly flattened, with pointed apex; ventral suture prominent.

_Prunus mahaleb_ is now a wild inhabitant of all southern Europe as far north as central France, southern Germany, Austria-Hungary and eastward through Asia Minor and Caucasia to and within the borders of Turkestan. Wherever it grows spontaneously in the Old World it is said to prefer rocky, gravelly, sunny slopes and the climate in which the grape thrives best. Wild or cultivated, the Mahaleb is a shallow-rooted plant, a fact that must be taken into consideration in its use as a stock. _Prunus mahaleb_ is a common escape from cultivation in eastern North America especially about the nursery centers of central New York.

The Mahaleb, or St. Lucie cherry, is of no importance to fruit-growers for its fruit but as a consort with nearly all of the Sweet and Sour Cherries now being propagated in North America it becomes of prime importance and so receives botanical consideration here. According to Schneider, in the reference cited, there are several spontaneous forms of _Prunus mahaleb_ and also several horticultural varieties grown as ornamentals. None of these, wild or cultivated, are of interest to fruit-growers, unless, perchance some one of them should prove to be a better stock upon which to work orchard cherries. Mahaleb stocks are usually grown as seedlings but may also be propagated from root cuttings.

The wood of the Mahaleb tree is of value in cabinet making, possessing among other good qualities a pleasant and lasting odor. The leaves, too, are odoriferous and are more or less used in France in the manufacture of perfumes and in cookery to give savor to sauces.

PRUNUS TOMENTOSA Thunberg.

1. Thunberg _Fl. Jap._ 203. 1784. 2. _Jack Garden & Forest_ =5=:580, fig. 99. 1892. 3. Bailey _Cyc. Am. Hort._ =3=:1451. 1901. 4. Schneider _Handb. Laubh._ =1=:601. 1906. 5. Koehne _Plantae Wilsonianae_ Pt. =2=:268. 1912.

_Cerasus tomentosa._ 6. Wallich _Cat._ No. 715. 1829.

A dwarfish, bush-like plant attaining a height of ten or twelve feet, vigorous, dense-topped, hardy; trunk and branches stocky; branches smooth, grayish-brown; branchlets many, of medium thickness and length, thickly overspread with short pubescence, with short internodes, roughish, with a few large, raised lenticels near the base.

Leaves numerous, two and one-eighth inches long, one and one-half inches wide, folded upward or flattened, broad-oval to obovate, velvety; upper surface dull, dark green, rugose; lower surface thickly pubescent, with a prominent midrib and veins; apex abruptly pointed; margin serrate; petiole three-sixteenths inch in length, reddish, pubescent, of medium thickness, with from twelve to fourteen small, globose, yellow glands, usually at the base of the blade.

Buds very small, short, pointed, free, arranged as lateral buds and in clusters on small, short spurs; leaf-scars not prominent; season of bloom early; flowers appear with the leaves, white, thirteen-sixteenths inch across; borne singly or in pairs; pedicels short, thick, glabrous; calyx-tube reddish, campanulate, glabrous; calyx-lobes narrow, acute, serrate, slightly pubescent, erect; petals white, roundish-ovate, entire, with short claws; anthers tinged with red; pistil pubescent at the base, longer than the stamens, often defective.

Fruit matures in mid-season; a half-inch in diameter, roundish, slightly compressed; cavity deep, narrow, abrupt; suture shallow; apex depressed, with adherent stigma; color currant-red; dots numerous, small, grayish, obscure; stem thickish, one-eighth to one-quarter of an inch in length, pubescent; skin thick, tender, adheres slightly to the pulp, covered with light pubescence; flesh light red, with light red juice, stringy, melting, sprightly, sour; good in quality; stone clinging, one-quarter of an inch long, one-eighth inch wide, oval, slightly pointed, with smooth surfaces.

The habitat of _Prunus tomentosa_ is probably Central Asia though it is now to be found growing spontaneously in East Tibet and the Chinese provinces of Setschuan, Hupe, Kansu and perhaps Tochlii.

This shrub-like cherry is very generally cultivated in central, eastern and northern China and in Japan for its fruit and as an ornamental. It has been introduced into cultivation in many widely separated places in North America and appears to be promising for cold regions, both bud and wood withstanding perfectly the most rigorous climates of the United States. As it grows in America it is a bush and never a true tree. It is a twiggy, close-jointed plant, usually with many stems springing from the ground and these bearing branches quite to the base. Frequently these low-growing branches bend to the ground and take root forming new plants. The bushes are thickly clothed with leaves densely tomentose on the underside, in this respect and in shape, as well, very unlike the foliage of common cultivated cherries. The flowers appear in great abundance with the leaves, making a handsome ornamental; they are white, becoming rose-colored as they fall away. The fruit ripens in mid-season for cherries, setting profusely from the many blossoms. The cherries are a half-inch in diameter, bright currant-red, covered with inconspicuous hairs and contain a stone of medium size. They are pleasantly acid, very juicy and withal a decided addition to cultivated cherries. _Prunus tomentosa_ seems a most promising plant for domestication and of particular merit for small gardens and cold regions.

Koehne, in his list of cherries, names ten botanical varieties of _Prunus tomentosa_. From this the species seems to be most variable and under cultivation would probably break up into many forms some of which might prove superior to the type species. Koehne's botanical varieties are given under the species on page 22.

PRUNUS PUMILA Linnaeus.

1. Linnaeus _Mant. Pl._ 75. 1768. 2. Bailey _Cor. Bul. Ex. Sta_. =38=:96. 1892. Bailey _l. c_. =70=:260. 1894. 3. Bailey _Cyc. Am. Hort._ =3=:1450. 1901.

_P. Susquehanae._ 4. Willdenow _Enum. Pl._ 519. 1809.

_P. depressa._ 5. Pursh _Fl. Am._ =1=:332. 1814.

_P. incana._ 6. Schweinitz Long's Expedition by Keating =2=:387. 1824.

_Cerasus glauca._ 7. Moench _Meth._ 672. 1794.

_C. pumila._ 8. Michaux _Fl. Bor. Am._ =2=:286. 1803.

_C. depressa._ 9. Seringe, in De Candolle _Prod._ =2=:538. 1825.

Plant a small shrub, five to eight feet in height, willow-like habit, weak, upright when young but becoming decumbent, slow-growing, hardy; trunk slender, smooth except for the raised lenticels; branches slender, smooth, twiggy, very dark, dull reddish-black with a tinge of gray; lenticels numerous, small, conspicuous; branchlets very slender, short, twiggy, with short internodes, dull grayish-brown, glabrous, with conspicuous, very small, raised lenticels.

Leaves hanging late in the season, small, averaging one and three-fourths inches long, one inch wide, flat, abruptly pointed, narrowly oblanceolate to obovate, thin; upper surface dark, dull green, smooth; lower surface light green, thinly pubescent on the midrib and veins; midrib small, straight; veins very minute; margin serrate, teeth tipped with very small glands; petiole short, one-fourth inch in length, glandless.

Flowers small, in two- to five-flowered umbels, white, appearing with the leaves; pedicels slender, a half-inch in length. Fruit nearly round, pendulous, variable in color but usually purple-black, without bloom, nearly a half-inch in diameter; flesh thin, variable in quality but often sour and astringent; season late July; stone turgid, nearly round.

_Prunus pumila_, the Sand Cherry, or Dwarf Cherry, of eastern America, is found on sandy and rocky inland shores from Maine to the District of Columbia and northwestward to the Lake of the Woods in Canada. In particular it is common on the sand dunes of the Great Lakes. Everywhere in the wild state it grows in light sands suggesting its use in arid soils and especially on poor soils in cold climates.

As yet there seem to be no named varieties of this cherry known to fruit-growers, its nearly related species, _Prunus besseyi_, offering greater opportunities to both the fruit-grower and the experimenter. Both the plants and fruits are so variable, the size, color and quality of the crop on some plants being quite attractive, that it is certain an opportunity to domesticate a worthy native plant is being overlooked. The species ought to have value, too, as a stock on which to work other cherries for sandy soils, dwarf trees and exacting climates.

PRUNUS CUNEATA Rafinesque.

1. Rafinesque _Ann. Nat._ 11. 1820. 2. Bailey _Cor. Ex. Sta. Bul._ =38=:101. 1892. 3. Britton and Brown _Ill. Flora_ =2=:250. 1897. 4. Gray _Man. Bot._ ed. =7=:498. 1908.

_P. pumila cuneata._ 5. Bailey _Cyc. Am. Hort._ =3=:1451. 1901.

_Prunus cuneata_, sometimes called the Appalachian cherry, is not growing at this Station but is described in the references given as very similar to the Sand Cherry, differing in the following respects:

The plant is dwarfer but is more erect never having prostrate branches; the branches are smoother and lighter colored; the leaves are shorter, more oval, more obtuse, thinner, less conspicuously veined, teeth fewer and the points more appressed; the flowers are larger, petals broader and are borne on slightly curled stems in umbels of two to four; the fruit and stone in the two species are much the same, possibly averaging smaller in this species.

The habitat of _Prunus cuneata_ is from Maine to North Carolina and northwest to Minnesota, being most commonly found in wet, stiff soils near lakes and bogs but often found on rocky hills if the soil be not too dry.

It is doubtful if this cherry is as promising for cultivation as the foregoing species and not nearly as worthy attention as the next cherry.

PRUNUS BESSEYI Bailey.

1. Bailey _Cor. Ex. Sta. Bul._ =70=:261. 1894. 2. _Contrib. U. S. Nat. Herb._ =3=:156. 1895. 3. Bessey _Neb. Hort. Soc._ =26=:168. 1895. Bessey _l. c._ =37=:121. 1906. 4. Britton and Brown _Ill. Flora_ =3=:251. 1897.

_P. pumila Besseyi._ 5. Waugh _Vt. Ex. Sta. Rpt._ =12=:239. 1898-99. 6. Bailey _Cyc. Am. Hort._ 3:1451. 1901.

Plant a small shrub, spreading or diffuse, one to four feet in height, open-centered, slow-growing, hardy; trunk slender, smooth; branches slender, smooth, very dark brownish-black, with numerous lenticels; branchlets slender, short, with short internodes, dull grayish-brown becoming almost black, smooth, glabrous, with conspicuous, small, raised lenticels.

Leaves hanging late, numerous, small, two and three-eighths inches long, one inch wide, thick, stiff, slightly folded upward or nearly flat; apex with a short taper-point, broadly lanceolate to nearly oval-lanceolate; upper surface dark green, glossy, smooth; lower surface very light green, not pubescent; midrib distinct, glabrous; veins small but distinct; margin serrate, teeth appressed, tipped with indistinct, sharp glands; petiole thick, three-eighths inch in length, glandless or with from one to two very small, light colored, globose glands on the petiole at the base of the leaf; stipules very prominent, almost leaf-like.

Flowers appearing with the leaves in sessile umbels, small, less than a half-inch across, white; fruit more than a half-inch in diameter, globose, sometimes oblong-pointed, yellowish, mottled or more often purple-black; variable in quality but always more or less astringent; ripening in early August; stone large, globose, slightly flattened.

The habitat of _Prunus besseyi_ is not yet definitely bounded but it can, at least, be said that this species is to be found on the prairies from Manitoba and Minnesota to southern Kansas and westward into Montana, Wyoming and Utah. In its natural range it undoubtedly runs into that of _Prunus pumila_ to the east, and Waugh, in the reference given, holds that the two species grade into each other and he, therefore, makes this a variety of the eastern species. Certainly _Prunus pumila_ and _Prunus besseyi_ are as distinct as are many other of the more or less indefinite species of this genus--few, indeed, are the species of Prunus that do not have outliers which overlap other types and, as we shall see, there are hybrids between this and species of other cherries, plums and even peaches and apricots, showing that the lines of demarcation between the members of this genus are difficult to define.

Although _Prunus besseyi_ has received attention from horticulturists less than a quarter-century it has aroused much interest, best indicated by the fact that now a considerable number of varieties of the species are under cultivation and there are more than a score of hybrids disseminated in which it is one of the parents. Indians, trappers and early settlers have long used the wild fruit under the name of Western Sand Cherry, Bessey's Cherry and Rocky Mountain Cherry. Among pioneers this cherry was held in high esteem for sauces, pies and preserves and, where there was a dearth of cultivated cherries, was eaten with relish out of hand. The flesh is tender, juicy and, while astringent as commonly found, plants bearing aromatic and very palatable cherries are often found growing wild while some of the domesticated plants bear very well-flavored fruits. All speak of the Sand Cherry as wonderful in productiveness and as having remarkable capacity to withstand the vicissitudes of the exacting climate in which it grows. A valuable asset of _Prunus besseyi_ is its great variability. Fruit from different plants varies in size, color and flavor suggesting that, under cultivation, amelioration will proceed rapidly. The plants of this species root freely from layers or root-cuttings and are therefore easily propagated and multiplied.

But it is in its hybrids that this western cherry has proved most valuable in horticulture. There are now hybrids under cultivation between this species and the Sand plum (_Prunus augustifolia watsoni_), the Hortulana plum (_Prunus hortulana_), the Simonii plum (_Prunus simonii_), the Japanese plum (_Prunus triflora_), the American plum (_Prunus americana_), the Cherry plum (_Prunus cerasifera_), the Sweet Cherry (_Prunus avium_), the peach (_Prunus persica_), the apricots _(Prunus armeniaca_ and _Prunus mume_), and the common plum _(Prunus domestica_). It would almost seem that this species is the "go-between" of the many and varied types of the genus Prunus. It is true that few of these hybrids yet shine as orchard plants but, given time, it seems certain that some will prove valuable in general horticulture and that many will be grown in the special horticulture of the northern Mississippi Valley and the adjoining plains to the west. Credit must be given to Professor N. E. Hansen of the South Dakota Experiment Station for most of our present knowledge of hybridism between this and other species.[10]

In his work with this species Hansen has also found that _Prunus besseyi_ makes a very good stock for peaches, apricots, Japanese and native plums and that, while it does not so readily consort with the true cherries, yet it can be used as a stock for them. On the other hand larger fruits of the Sand Cherry can be grown when it is budded on stocks of the Americana.

[10] See bulletins 87 (1904), 88 (1904), 108 (1908) and 130 (1911) from the South Dakota Experiment Station, Brookings, S. D.

MINOR SPECIES

Besides these well-recognized species of cultivated cherries there are several others that play a much less conspicuous part in horticulture. _Prunus fruticosa_ Pallas, the Dwarf Cherry of Europe, is much cultivated, more especially its botanical variety _pendula_, as an ornamental and somewhat for its fruit. According to Wilson,[11] _Prunus involucrata_ Koehne is grown for its fruit in the gardens of China; the fruits, he says, are "small and lacking in flavour." The fruits of _Prunus emarginata_ Walpers are eaten by the Indians on the Pacific Coast and the early settlers used the species as a stock for orchard cherries. _Prunus jacquemontii_ Hooker, the Dwarf Cherry of Afghanistan and Tibet, is occasionally in culture for its fruit and as a park plant; so also is another dwarf cherry from southwestern Asia, _Prunus incana_ Steven. _Prunus pseudocerasus_ Lindley, the Flowering Cherry of Japan, is a well-known ornamental the world over and in Japan is used as a stock for orchard cherries for which purpose, as we have suggested in the discussion of stocks, it ought to be tried in America.

[11] Wilson, E. H. _A Naturalist in Western China_ =2=:27. 1913.