Part 15

The eggs she lays are very small, conical objects, about the twenty-fifth part of an inch long, white at first, but in two or three days turning yellow, and then just before the time of hatching they become a dull grey. If one of these eggs is examined with a microscope it is seen to be covered with a beautiful net-work of raised lines, the longitudinal lines appearing like ribs joined together by cross lines, and coming together at the apex. The lower part of the egg, by which it adheres to one of the leaf-ribs on the under side of the leaf, is flattened, giving the egg the appearance of a truncated cone, or of one of those conical bullets, which are used in breech-loading rifles. If the reader will look at fig. 11, _a_, he will see a magnified representation of the egg, showing the longitudial ribs and cross lines; and at _c_, the egg of natural size, attached to the rib on the under side of the leaf, just as the butterfly places it.

In about a week after the butterfly has deposited the egg, there hatches from it a very small caterpillar, not more than the tenth of an inch long. It however grows very rapidly, and soon becomes too large for its jacket. But its jacket is very accommodating, and when the little fellow has got tired of it and wants a new one, the old one splits down the back, so that he can crawl out of it with a new jacket on, and looking as bright and gay as any new suit. And now it is a very pretty little creature, with transverse bands of black, yellow, and white, and a pair of black horns near the head, and another pair not quite so long near the other end. If it is examined with a microscope a few black hairs will be seen on each segment; these are shown at _e_ and _f_ in fig. 11.

The caterpillar seems to eat as though eating was the sole purpose of its life, and in consequence it increases in size very rapidly, so that it is obliged to crawl out of its skin twice more before it has attained its full size. This process of changing its coat is called moulting. Just before each moult it ceases to eat for a few hours, but as soon as that process is over, it falls-to again with greater voracity than ever. At each moult the black fleshy horns become longer. The new horns are nicely folded up under the skin, as can be seen at _d_, fig. 11, but soon grow straight after the old skin has been cast off.

If any of our readers, the younger readers especially, have a desire to begin the study of entomology, they will find this insect a very interesting subject with which to make a beginning. The writer can well remember his excursions to a neighboring field overgrown with milkweeds, when he had scarce attained to the dignity of pantaloons, in search of these beautiful larvæ. These he gathered in considerable numbers, confined them in a box, and watched with delighted interest the various metamorphoses they underwent. Those who have never witnessed them, if they have any taste for the study, will be surprised and greatly gratified to watch the changes undergone in the progress from the egg to the butterfly. The creature is of such a size, and so beautiful in all its stages, that there is no difficulty in seeing it at all times, and each step adds some new feature of interest.

When the caterpillar has attained its full size it will be about an inch and three quarters in length, and will have the appearance shown in fig. 12. The markings are very distinct. Each segment has a transverse band of black in the centre, bordered on each side with white, with a yellow band between. After it has reached this stage of its life it ceases to eat, and presently begins to roam about in search of a suitable place to undergo its next change. And a wonderful change it is; instead of a hungry creeping creature, eating voraciously night and day, it is about to fasten itself to a spot from which it can not move, and pass into a condition in which it will have neither mouth to eat with, nor feet with which to walk. To all outward seeming it will have ceased to live; cold, and stiff, and motionless, it will manifest no sense of feeling whatever, nor any symptom of life.

Having found a place suitable for the metamorphose about to take place, which will always be the underside of some convenient support, the caterpillar proceeds to cover a considerable space, a diameter of three or four inches, with fine, white, silken threads, which it spins from its mouth, or from spinnarets placed at the mouth. These silken threads are laid on thicker and thicker towards the centre of the chosen spot, and at the centre a small pointed knob is raised of the same material. All this is done in order that the creature may suspend itself, head downwards, and hang securely by this silken knob without danger of being torn by its weight from its fastenings. Having completed all these arrangements, it proceeds to suspend itself by fastening the hooks on the pair of feet upon the last or anal segment into the silken knob, and when these are secured lets go its hold of the silken carpet with all the other feet and hangs suspended in mid-air, from the underside of some fence rail, or horizontal bar, or if in confinement, from the lid of the box or ceiling of the room.

What strange spell is upon the creature that it leaves its food, which a short time ago was all its desire, and travels off in search of some hidden retreat, some lonely nook? And why is it now travelling round and round within the circumference of a few inches upon the ceiling, laying down so carefully such a network of silken threads? Who has told it to lay them down increasing in thickness from the circumference to the centre? And now it has ceased to travel about, and has stationed itself with its head in the centre of its silken carpet; if you will watch it closely, you will see that it is yet spinning, and now and then it moves its head to the right and left, about as far as it can conveniently reach. As you look you see a little projection is being built up directly under its head, and that these motions to the right and left are made in the act of laying down some anchoring cables that shall fasten it securely to the web or carpet it has fastened upon the ceiling. What schoolmaster taught it that a cone is the strongest form in which it can arrange its gossamer threads? And who told it to go and hang itself thereby, suspended from its hindermost feet? Does it know the future that is before it; the life that lies beyond this gateway of seeming death? (_Continued in next No._)

=VOL. I.]= =OCTOBER, 1878.= =[NO. 10.=

THE ARCHIPPUS BUTTERFLY.

(_Danais Archippus._)

If our readers will look at fig. 13, _a_, they will see how the caterpillar appears after it has suspended itself. Yet it is not motionless, but keeps continually stretching forth its head and bringing it in again, with very much the same motion as is made while feeding, with the edge of the leaf between its claws, beginning as far from itself as it can reach, and cutting it down as it draws the head in towards the body. What this movement of the head has to do with the changes that are going on within its body we can not say, but for some reason it keeps up this motion with very little intermission until it is ready to cast off its skin. The approach of this event may be known by its shrivelled appearance, the fleshy horns have become withered and almost dry looking, and the skin is wrinkled and thin. The caterpillar occasionally draws itself up and strains itself, until it succeeds in bursting the skin on the back not far from the head. And now commences a series of movements very difficult accurately to describe, but wonderful to look upon. The creature stretches and contracts its body with an astonishing rapidity, and at each movement forces the skin upwards, until it has reached the spot from which it is suspended. At the hinder, or what is now the upper, end of the body, there has been formed beneath the skin a black little spike, crowned at the extremity with a number of little hooks by which it is to fasten itself to the silken knob from which it is hanging. To withdraw this black spike from the shrivelled skin that envelopes it, and fasten its hooks into the little knob, so that it can hang there while the skin falls to the ground, is the feat now to be performed.

Fig. 13, _b_, represents the creature at this most interesting and critical moment. How shall it sustain itself in mid-air while this is being done? It has neither hands, nor feet, nor mouth by which to hold on and keep itself from falling. And yet it will do this very thing, and though the writer has witnessed this performance probably not less than a thousand times, he has never seen it fail to succeed. Who taught this creature how?

Look now at fig. 13, _c_, and you will learn how it is done. It seizes a portion of the skin between the joints of the upper portion of the body, and compressing the joints together, holds securely by the skin while it withdraws the black spike, and bending it over the mass of skin fastens the hooks with which the point is armed into the silken knob, and then, letting go of the skin, it wriggles itself about, bedding the hooks more securely in the silk, and working the skin loose from its fastening until it drops to the ground.

When this has been accomplished, it ceases its hurried movements, as though wearied by its own exertions, and slowly contracts the upper segments until it assumes the appearance shown in fig. 14. In a little while it will have become quite hard and motionless. If you touch it, there will be no evidence that it feels your touch, and to you it will feel cold and lifeless. But it is a pretty object to look upon, of a beautiful pale-green, dotted with gold, with a crimped band of gold margined with black more than half way around the body; it seems to be a casket containing something of more than common interest.

In about a week the chrysalis will begin to change its color, gradually growing darker until the green is entirely gone, and the colors of the butterfly within can be distinctly seen through its now transparent walls. The butterfly is now ready to come out of its prison, and while you are watching it a sudden crackling noise announces the fact that the chrysalis has been split, and the head and fore legs of the butterfly begin to appear, followed very speedily by the whole body. And it looks almost as if it were all body, for the wings are very small indeed, and seem to be but mere rudiments of wings, wholly unsuited to the purpose of supporting such a body in the air. The butterfly now seeks a place where the wings can hang freely, often remaining hanging to the empty chrysalis, or under surface of some support, to which it fastens by means of its claws. In this position the wings grow with a rapidity that is most marvellous. They are not folded up and merely unfolded, but actually grow from the size of the wings of a large bee until they measure four inches across, and that within thirty minutes.

The appearance of the butterfly when its wings are fully grown may be seen at fig. 15. The ground color of the wings is a bright orange-red, margined with black, and dotted with white spots in the black border.

We have given this account of the history of this insect, not because it does any injury to our crops of fruit or grain, but because its history illustrates the metamorphoses of many other insects, and any who wish can easily rear it in confinement, and watch the changes it undergoes.

—————

RISE AND FALL OF SAP.

It is a very commonly received idea that the sap of trees descends in autumn, and when the leaves fall, returns to the roots whence it came in the spring. It does not seem to have once occurred to those who accept this view of the matter, that there would be any difficulty in cramming a quart of water into a pint cup; perhaps, in order to accommodate the sap, the roots are supposed to be as large and capacious as the trunk and head of the tree; in short, that there is as much tree underground as above. Whence the idea sprang into existence that the sap retires to the roots on the approach of winter, it is not now possible to say, but its very general popular acceptation is an evidence of the way in which false views gain currency because some one ventures to make the assertion, and the public mind stops not even to weigh the probabilities, much less to investigate the ground upon which it rests. Surely the time has come when we should cease to accept assertions upon trust, and demand the facts on which they are based. Having these, we can consider the theory, and if it does not suit us we can make one for ourselves.

Now, in this matter of the sap, by which we mean all the fluids which are contained in the interior of a tree, the facts are these: if the trunk be cut in spring, the sap will run out; in summer, autumn, and winter it will not, except under exceptional circumstances. But nevertheless the sap is in motion in the summer and autumn, and winter too; nay, save when extreme cold may for a time interfere with its flow, it is always in motion; and the reason why it runs out of the trunk in the spring is because it is then present in much greater abundance than at any other season of the year. During the summer, when the tree is covered with foliage, the leaves are evaporating large quantities of the fluid parts of the tree into the air, while another portion is being elaborated and converted into the tissues and structure of the tree, producing what we call growth. When the autumn has come, what with the evaporation and solidification that has taken place, the interior of the tree has become comparatively dry, so that the quantity of sap has become so greatly diminished that it no longer exudes when an incision is made. Our readers are, at least many of them, aware that if a branch be cut off from a grape vine in spring when the buds are starting, the sap will run out quite freely, producing what is called bleeding; but if the same branch were allowed to remain until the leaves on the vine have became fully expanded, then if it be cut off no bleeding will take place. The reason is, that the evaporation which is taking place in the leaves has exhausted the supply of sap to such an extent that there is no surplus in the vine to escape in that way.

The leaves being the principal organs of assimilation and perspiration, it follows that when they have fallen off there is no longer much loss of fluid to the tree from these causes. But the power of the roots to absorb moisture from the earth is not diminished by the loss of the leaves; they continue to draw fluid from the earth, and to send it up into the tree. This action continues, except as modified by extreme cold, all winter; the fluids are drawn from the soil by the roots and sent into the tree, and by the time that spring has come the tree is full of fluids and every vessel distended with sap. During the winter we are not able to find sap by cutting the tree, because the process of filling with fluid is gradual.

M. Biot, many years ago, made some very interesting experiments on the flow of sap, and made a contrivance by which the rate of motion could be measured at any season, and showed that there was considerable activity even in winter. He found that the direction in which the sap moved was very considerably affected by frost. When the weather was mild the sap was always ascending; but when it was freezing weather the sap flowed down. This he attributed to the contraction of the sap-vessels by the cold, which forced the sap into the larger vessels which were unaffected by the frost under ground. When, however, the frost was sufficiently severe and continued to reach the roots, then the sap was forced back into the trunk; but when it came on to thaw and the frost left the ground, the sap returned to the roots. Thus we see that, as a rule, the sap is always ascending, and that when it descends it is because it is forced to do so by some temporary cause, and when that cause ceases to act the sap immediately begins to ascend again.

In connection with the supposed ascent of the sap in spring, and growing out of it, is the popular idea that this ascent of the sap is the cause of the expansion of the buds and leaves. It would be nearer the truth to say that the expansion of the buds and leaves was the cause of the motion of the sap. Any of our readers can make the following experiment for themselves, and see the true state of the case. If a tree be cut into or tapped in some of the upright branches near the top very early in the spring, and be again tapped just below the branches on the trunk, and again just above the surface of the ground, it will be found that the sap will flow from the wound that is nearest to the top first, from the one just below the branches next, and last of all from the one near the ground. The reason for this is, that the light and warmth tell first upon the excitable buds at the extremities of the tree, and therefore the sap is set into an accelerated motion that lies nearest to them. The gentleman who first made this discovery came to the conclusion that in the spring the sap of trees descended instead of ascending, but he forgot that the moment the buds begin to expand they draw the sap from the parts nearest to them; this causes the sap just beyond to push upwards to supply the place of that taken up by the buds, and as the buds increase and expand is this absorption increased, and the circle of motion enlarged from the buds downwards.

Were it not true that the sap is constantly ascending, we should lose all our evergreens during the very first winter, for the evaporation that goes on in winter from their leaves would soon season the wood of the tree were it not made good from the roots below; and hence it is that some evergreens are killed by a severe winter while they are small, which would survive without injury had they attained to a greater size; for, being small, the roots have not penetrated to sufficient depth to reach below the frozen ground, and consequently can not draw from the frozen earth in sufficient quantity, nor with sufficient rapidity, to supply the waste by evaporation; whereas when larger the roots will have penetrated quite below the reach of frost, and will be able to draw from the soil sufficient moisture to supply the loss.

—————

TOMATOES.

Messrs. John A. Bruce & Co., seedsmen, of Hamilton, give considerable attention to the testing of the different varieties of vegetables, and after thorough trial find in their experience that Hubbard’s Improved Curled Leaf is the earliest. It is small compared with many of the later sorts, and the plant is of a dwarf habit. Next to this they place the Early Conqueror, which is of good size, and very uniform in shape. Then the General Grant, a firm fleshed, bright crimson, productive variety, for the main crop; and after it the Trophy, for a later variety, one of the largest and best flavored of them all. These four sorts, ripening in the order named, they consider the best market sorts. We have found the General Grant very productive, and to ripen its fruit rapidly after it once begins to come in.

—————

THE MONTREAL HORTICULTURAL SOCIETY, AND FRUIT GROWERS’ ASSOCIATION OF PROVINCE OF QUEBEC.

It is gratifying to learn that our sister Province of Quebec has succeeded in organizing a provincial association similar to our own, and standing in a similar relation to the government. It has a double existence, arising from its union with the Montreal Horticultural Society, and, as that society, it holds an annual exhibition in the City of Montreal, with a city membership paying an annual fee of two dollars, while, as the Fruit Growers’ Association, it publishes an annual report, as an appendix to the provincial agricultural report, and charges the rural members one dollar per year.

Will it seem boastful to say that, from the experience of what has been done in Ontario, we are confident a career of great usefulness is opening up before our sister society; that a vast amount of useful information locked up in individual experiences will now be brought out, and made the common stock of all; that many valuable seedling fruits will be brought from their modest retirement and disseminated, to enrich the orchards and gardens of the whole Province; that a medium of communication will be established between all the fruit growers, that will make them to know and esteem each other, and stimulate to harmonious efforts for the advancement of pomology; and that an increased impetus will be given to the cultivation of fruits, to the originating of new and valuable varieties, and the diffusion of information on all matters involved in the growing of superior fruit.

There is no department of the work accomplished by these associations more productive of benefit to all, than the meetings for discussion of topics in which all have an interest. By means of these discussions, the experiences of many practical cultivators are brought together, and whether they are experiences of success or failure, they throw light on the subject, and serve either as beacon lights to give warning of the danger, or as finger posts to guide into the best and safest way. Many have been saved the trouble and vexation of testing worthless varieties, the experience of one being made the experience of all. Again, when a fruit has proved itself valuable in the hands of one cultivator, there is reason to believe that it will also be valuable in the hands of many.

These meetings for discussion will be the more interesting and valuable the more those who attend them accurately observe the facts that come within the range of their individual observations and experiences, and come to the meetings prepared to impart what they have gathered. We remember hearing a very successful grower of grapes say, when asked about the cultivation of them, that he did not know anything about growing grapes. The trouble with him was that he supposed that everyone knew all that he did on the subject, and merely meant that he had no special method peculiar to himself. He was far too modest; experience had taught him much that others did not know, and it is the giving out of this experience from all that increases the knowledge of all.

—————

THE GRAVENSTEIN APPLE.

Those readers of the CANADIAN HORTICULTURIST who are best acquainted with this apple, will fully corroborate anything that can be said in its praise. It derives its name from the place of its birth, Gravenstein, in Holstein, Germany, and has the reputation of being one of the best apples of Northern Europe. The reputation it enjoys there has been fully maintained by it in America, and here it ranks as one of our very best and most valuable October apples. It has been widely disseminated throughout the Dominion, and is highly esteemed. The trees thrive well in Nova Scotia, and certainly in a large part of Ontario, having been reported as bearing fruit in the county of Renfrew. They are of an upright habit, stout bodied, and form large, spreading heads; come into bearing early, and are very productive.