CHAPTER VIII

THE MAIDEN HAIR TREE

'...the trees That whisper round a temple become soon Dear as the temple's self.' Keats.

The Maiden Hair tree of China and Japan, which was introduced into Europe early in the eighteenth century, has now become fairly well known. Though hardy in England, it requires warmer summers for full development and regular flowering. To botanists this Eastern tree is of peculiar interest, partly because of the isolated position it occupies in the plant-kingdom and partly by reason of its great antiquity. There is probably no other existing tree which has so strong a claim to be styled a 'living fossil,' to use a term applied by Darwin to survivals from the past. In 1712 the traveller Kaempfer proposed for this plant the generic name Ginkgo, and Linnaeus adopted this designation, adding the specific name _biloba_ to denote the bisection of the wedge-shaped lamina of the leaf into two divergent segments. In 1777 the English botanist Sir J. E. Smith expressed his disapproval of what he called the uncouth name Ginkgo by substituting for _Ginkgo biloba_ the title Salisburia adiantifolia, but as it is customary to retain names adopted or proposed by Linnaeus, the founder of the binominal system of nomenclature, the correct botanical designation of the maiden hair tree is _Ginkgo biloba_. Mere personal preference such as that of Sir J. E. Smith for Salisburia is not an adequate reason for rejecting an older name.

In its pyramidal habit Ginkgo agrees generally with the larch and other Conifers. Like the larch and cedar it possesses two kinds of foliage shoots, the more rapidly growing long shoots with scattered leaves and the much shorter dwarf-shoots which elongate slightly each year and bear several leaves crowded round their apex. The leaves (Fig. 19), which are shed each year, are similar in the cuneate form of the lamina and in the fan-like distribution of the forked veins, to the large leaflets of some species of maiden hair ferns: the thin lamina carried by a slender leaf-stalk is usually about 3 inches across, though in exceptional cases it may reach a breadth of 8 inches. The lamina is usually divided by a deep =V=-shaped sinus into two equal halves; it may be entire with an irregularly crenulate margin, or, on seedlings and vigorous long shoots, the lamina may be cut into several wedge-shaped segments.

The male and female flowers are borne on separate trees; the male consists of a central axis giving off slender branches, each of which ends in a small terminal knot and two elliptical capsules in which the pollen is produced. The female flowers have a stouter axis which normally produces two seeds at the apex. The seed is encased in a green fleshy substance and, as in the fruit of a cherry or plum, the kernel is protected by a hard woody shell. In the form of the leaves and in the structure of the flowers Ginkgo presents features which clearly distinguish it from the Conifers, the class in which, until recently, it was included. In 1896 the Japanese botanist Hirase made the important discovery that the male reproductive cells of Ginkgo are large motile bodies provided with a spirally coiled band of minute cilia--delicate hairs which by their rapid lashing-movement propel the cell through water. In all Flowering Plants and in Conifers the male reproductive cells have no independent means of locomotion; they are carried to the female cell by the formation of a slender tube--the pollen-tube--produced by the pollen-grain. In the Ferns, Lycopods and Horsetails--in fact in all members of the Pteridophyta--as also in the Mosses and Liverworts as well as in many of the still lower plants, the male cells swim to the egg by the lashing of cilia like those on the male cells of Ginkgo. This difference in regard to the nature of the male cells was considered to be a fundamental distinction between the higher seed-bearing plants and all other groups of the vegetable kingdom. It was, therefore, with no ordinary interest that Hirase's discovery was received, as it broke down a distinction between the two great divisions of the plant-world which had been generally accepted as fundamental; though it is only fair to say that the German botanist Hofmeister, a man of exceptional originality and power of grasping the essential, foresaw the possibility that this arbitrary barrier would eventually be removed. The Ferns and other plants in which the male cells are motile, represent earlier stages in the progress of plant development, when the presence of water was essential for the act of fertilisation, a relic of earlier days when the whole plant-body was fitted for a life in water. As higher types were produced, the plant-machinery became less dependent on an aqueous habitat, and the loss of organs of locomotion in the male cells is an instance of the kind of change accompanying the gradual adaptation to life on land. The idea of the gradual emancipation of plants from a watery environment is expressed in a somewhat extreme form by the author of a book entitled _The Lessons of Evolution_(52), who states that the ocean is the mother of plant-life and that plants formed the army which conquered the land. In Ginkgo we have a type which, though similar in most respects to the Conifers, possesses in its motile reproductive cells a persistent inheritance from the past. The recognition of this special feature afforded a sound reason, especially when other peculiarities are considered, for removing Ginkgo from the Conifers and instituting a new class-name, Ginkgoales.

Ginkgo is a generalised type, linked by different characters both with living members of the two classes of naked-seeded plants and with certain existing Palaeozoic genera. It is a survivor of a race which has narrowly escaped extinction; the last of a long line that has outlived its family and offers by its persistence an impressive instance of the past in the present. Though Mrs Bishop in her _Untrodden Paths in Japan_ speaks of forests of Maiden Hair trees apparently in a wild state, it is generally believed that they were cultivated specimens. Mr Henry who has an exceptionally wide knowledge of Chinese vegetation tells us that 'all scientific travellers in Japan and the leading Japanese botanists and foresters deny its being indigenous in any part of Japan; and botanical collectors have not observed it truly wild in China.' Moreover, Mr E. H. Wilson, after traversing the whole of the district where Ginkgo was supposed to occur in a wild state, says that he found only cultivated trees. There is no reason to doubt that China is the last stronghold of this ancient type which in an earlier period of the earth's history overspread the world.

A brief summary of the past history of Ginkgo and of the Ginkgoales supplies overwhelming testimony to the tenacity of life with which the Maiden Hair tree has persisted through the ages.

It was pointed out in the account of the past history of Araucaria that the records obtained from Palaeozoic rocks, while affording evidence of the existence of Carboniferous and Permian genera undoubtedly allied to the living species, do not enable us to speak with certainty as to the precise degree of affinity. Similarly, Palaeozoic leaves have been described as representatives of the class of which Ginkgo is the sole survivor, but the evidence on which this relationship is assumed is by no means conclusive.

The generic name Psygmophyllum has been applied to some impressions of Ginkgo-like leaves discovered in the Upper Devonian rocks of Bear Island, a small remnant of land in the Arctic circle, which has furnished valuable information as to the composition of one of the oldest floras of which satisfactory remains have been found. Other examples of these lobed, wedge-shaped leaves are recorded from Carboniferous rocks in Germany, France, and elsewhere; from Permian strata in the east of Russia and from Palaeozoic beds in Cape Colony and Kashmir. A relationship between Psygmophyllum and Ginkgo is, however, by no means established and rests solely on a resemblance in the form of the leaves. The close correspondence in form and venation between some leaves from Permian rocks in the Ural mountains and from Lower Permian beds in France, and those of the recent species, is considered by some authors sufficiently striking to justify the reference of these fossils to the genus Ginkgo. Similar leaves of Permian age, which may also be related to the existing species, have been described under the name Ginkgophyllum. Other specimens of Palaeozoic age from North America and elsewhere have been assigned to the Ginkgoales; but in none of these cases, despite the resemblance in leaf-form, is there sufficiently convincing evidence of close relationship to warrant a definite assertion that the plants in question were members of the group of which Ginkgo alone remains.

It is, however, an undoubted fact that the Maiden Hair tree is connected by a long line of ancestors with the earliest phase of the Mesozoic era. From many parts of the world large collections of fossil plants have been obtained from strata referred to the Rhaetic period, or to the upper division of the Triassic system. A comparison of floras from these geological horizons in different parts of the world points to a vegetation extending from Australia, Cape Colony, and South America, to Tonkin, the south of Sweden and North America, which was characterised by a greater uniformity than is shown by widely separated floras at the present day. One of the commonest genera in Rhaetic floras is that known as Baiera; this name is applied to wedge-shaped leaves with a slender stalk similar in shape and venation to those of Ginkgo, but differing in the greater number and smaller breadth of the segments. Between the deeply dissected leaf of a typical Baiera with its narrow linear lobes and the entire or broadly lobed leaf of a Ginkgo there are many connecting links, and to some specimens either name might be applied with equal fitness. Examples of Baiera leaves, in some cases associated with fragments of reproductive organs, are recorded from Rhaetic rocks of France, the south of Sweden, Tonkin, Chili, the Argentine, North America, South Africa, and from other regions. There is abundant evidence pointing to the almost world-wide distribution of the Ginkgoales, as represented more especially by Baiera, in the older Mesozoic floras. In the later Jurassic rocks of Yorkshire true Ginkgo leaves as well as those of the Baiera type are fairly common; with the leaves have been found pieces of male and female flowers. Ginkgo and Baiera have been described from Jurassic rocks of Germany, France, Russia, Bornholm, and elsewhere in Europe; they occur abundantly in Middle Jurassic rocks in northern Siberia, and are represented in the Jurassic floras of Franz Josef Land, the East Coast of Greenland, and Spitzbergen (Fig. 20). The abundance of Ginkgo and Baiera leaves associated with male flowers and seeds discovered in Jurassic rocks, approximately of the same geological age as those on the Yorkshire coast, in East Siberia and in the Amur district, has led to the suggestion that this region may have been a centre where the Ginkgoales reached their maximum development in the Mesozoic period.

It should be added that other genera of Jurassic and Rhaetic fossils in addition to Ginkgo and Baiera have been referred to the Ginkgoales, though evidence of such affinity is not convincing. There is, however, good reason to believe that this widespread group was represented by several genera in the older Mesozoic floras.

The occurrence of the Ginkgoales in Jurassic rocks in King Charles Land and in the New Siberian Islands (lat. 78° and 75° N.), in Central China, Japan, Turkestan, California, Oregon, South Africa, Australia, and Graham's Land demonstrates the cosmopolitan nature of the group. During the later part of the Jurassic period and in the Wealden floras both Baiera and Ginkgo were abundant; leaves are recorded from Jurassic strata in the north-east of Scotland, from Lower Cretaceous or Wealden rocks in North Germany, Portugal, Vancouver Island, Wyoming, and Greenland.

During the Tertiary period, or probably in the earlier days of that era. Ginkgo flourished in North America, in Alaska and in the Mackenzie River district, Greenland, Saghalien Island, and in several European regions. In Chapter III reference was made to the volcanic activity which characterised the north-west European area in the early Tertiary period and resulted in the formation of the thick sheets of basalt on the north-east coast of Ireland and in the Inner Hebrides. There were occasional pauses in the volcanic activity, during which vegetation established itself on the weathered surface of the lava, and left traces of its existence in the leaves and twigs preserved in the sedimentary material enclosed between successive lava-floras. At Ardtun Head in the Isle of Mull beautifully preserved leaves of Ginkgo, 2-4 inches in breadth, with the median sinus and the venation characteristic of the leaves of the existing plant, have been discovered in a bed of clay which marks the site of a lake in a depression on the lava-plateau. The resemblance of these Tertiary leaves from Mull to those of the surviving Maiden Hair tree is so close as to suggest specific identity. Mr Starkie Gardner and Baron Ettingshausen have described some seeds from the London clay (Lower Tertiary) in the Isle of Sheppey as those of Ginkgo, but this identification rests on data too insufficient to be accepted without hesitation.

The recent cultivation of _Ginkgo biloba_ in Britain may therefore be spoken of as the re-introduction of a plant which in the earlier part or in the middle of the Tertiary period flourished in the west of Scotland, and was abundant in England in the earlier Jurassic period. It is impossible to say with any confidence where the Ginkgoales first made their appearance, whether in the far north or in the south, nor are we able to explain the gradual decline of so venerable and vigorous a race.

As we search among the fragmentary herbaria scattered through the sedimentary rocks in that comparatively small portion of the earth's crust which is accessible to investigation, we discover evidence of a shifting of the balance of power among different classes of plants in the course of our survey of successive floras. Plants now insignificant and few in number are found to be descendants of a long line of ancestors stretching back to a remote antiquity when they formed the dominant class. Others which flourished in a former period no longer survive, either themselves or in direct descendants. 'The extinction of species has been involved in the most gratuitous mystery.' We can only speculate vaguely as to the cause of success or failure. Certain types were better armed for the struggle for life, and produced descendants able to hold their own and to perpetuate the race through the ages in an unbroken line. Others had a shorter life and fell out of the ranks of the advancing and ever changing army. To quote Darwin's words:'We need not marvel at extinction; if we must marvel, let it be at our own presumption in imagining for a moment that we understand the many complex contingencies on which the existence of each species depends.'

BIBLIOGRAPHY

Many of the books and papers dealing with subjects touched upon in this volume are not included in the following list. For reference to a more complete bibliography the reader should consult more technical treatises.

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4. The Historie of the World, commonly called the Naturall Historic of the C. Plinius Secundus. Translated into English by Philemon Holland. London, 1634.

5. Hooker, J. D. On Three Oaks of Palestine. _Trans. Linnean Society_, Vol. XXIII. p. 381. 1862.

6. Holtermann, Carl. Der Einfluss des Klimas auf den Bau der Pflanzengewebe. Leipzig, 1907.

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8. Huxley, T. H. Man's Place in Nature and other Anthropological Essays. _Collected Essays_, Vol. VII. (On the methods and results of Ethnology.) London, 1901.

9. Lewis, F. J. The sequence of Plant Remains in the British Peat Mosses. _Science Progress_, No. 6. October, 1907.

10. Strahan, A. On submerged Land-surfaces at Barry, Glamorganshire. With notes on the Fauna and Flora by Clement Reid; etc. _Quart. Journ. Geological Society_, Vol. LII. p. 474. 1896.

11. The Life and Letters of Charles Darwin. Edited by Francis Darwin. 3 Vols. London, 1887.

12. More Letters of Charles Darwin. Edited by Francis Darwin and A. C. Seward. 2 Vols. London, 1903.

13. Ward, Lester F. The Course of Biologic Evolution. Anniversary Address of the President of the Biological Society. Washington, 1890.

14. Marshall, W. _Anacharis alsinastrum_, a new water weed. (Reprinted from the Cambridge _Independent Press_.) London, 1852.

{ Bailey, C. Notes on the structure, the occurrence in { Lancashire, and the source of origin, of _Naias gramineus_ { Delile, var. _Delilei magnus_. _Journal of Botany_, { Vol. XXII. p. 305. 1884. 15. { { Weiss, F. H. and H. Murray. On the occurrence and { distribution of some alien aquatic plants in the Reddish { Canal. _Mem. Proc. Manchester Lit. and Phil. Society_, { Vol. LIII. Pt. II. 1909.

16. Bennett, A. The Halifax Potamogeton. _Naturalist_, No. 621. October, 1908.

17. Hooker, J. D. Outlines of the Distribution of Arctic Plants. _Trans. Linn. Soc._ Vol. XXIII. p. 251. 1862.

18. Engler, A. Plants of the Northern Temperate Zone in their transition to the High Mountains of Tropical Africa. _Annals of Botany_, Vol. XVIII. p. 523. 1904.

19. Darwin, C. The Origin of Species. London, 1900.

20. Ridley, H. N. On the dispersal of seeds by wind. _Annals of Botany_, Vol. XIX. p. 351. 1905.

21. Hooker, J. D. On the Cedars of Lebanon, Taunus, Algeria, and India. _The Natural History Review_, 1862, p. 11.

22. Forbes, E. On the connection between the distribution of the existing Fauna and Flora of the British Isles, and the geological changes which have affected their area.... _Memoirs, Geological Survey_, Vol. I. p. 336. 1846.

23. Praeger, R. L. The Wild Flowers of the West of Ireland and their history. _Journ. R. Hort. Soc._ Vol. XXXVI. p. 299. 1910.

24. Ernst, A. The New Flora of the Volcanic Island of Krakatau. Translated by A. C. Seward. Cambridge, 1908.

25. Praeger, R. L. A Tourist's Flora of the West of Ireland. Dublin, 1909.

{ Rendle, A. B. _Sisyrinchium californicum_ Dryand. 26. { _Journal of Botany_, Vol XXXIV. p. 494. 1896. { Marshall, E. S. _Sisyrinchium californicum_ in Ireland. { _Ibid._ p. 366.

{ Reid, Clement. The Origin of the British Flora. London, 1899. 27. { Reid, Clement and Eleanor M. On the Pre-glacial { Flora of Britain _Journ. Linn. Soc._ Vol. XXVIII. p. 206. { 1908.

28. Lankester, Sir Edwin Ray. Mature and Man. The Romanes Lecture. Oxford, 1905.

29. Huxley, T. H. On a Piece of Chalk. _Collected Essays_, Vol. VIII. London, 1896.

30. Jukes-Browne, A. J. The Building of the British Isles. London, 1911.

31. Ray, J. Three Physico-Theological Discourses, etc. (2nd Edition.) London, 1693.

32. Woodward, J. An Essay toward a Natural History of the Earth. London, 1695.

33. Sollas, W. J. The Age of the Earth, and other geological studies. London, 1905.

34. Ward, L. F. Status of the Mesozoic Floras of the United States. _Monograph 48, U. S. Geol. Surv._ 1905.

35. Arber, E. A. Newell. _Cupressinoxylon Hookeri_ sp. nov., a large silicified tree from Tasmania. _Geological Magazine_, Vol. I. [V.], p. 7. 1904.

{ 1. Holmes, W. H. Fossil Forests of the Volcanic Tertiary { Formations of the Yellowstone National Park. Ann. { Rep. Geol. and Geogr. Surv. (U.S.A.), 1878, Pt. II. p. 47. 36. { 2. Knowlton, F. H. Fossil Flora of the Yellowstone { National Park. _Monograph 32, U. S. Geol. Survey_, { Pt. II. 1899.

37. Darwin, C. Journal of Researches into the Natural History and Geology of the countries visited during the voyage round the world of H.M.S. 'Beagle.' London, 1902.

38. Dufferin, Lord. Letters from High Latitudes. London. N.D.

39. Amundsen, R. The North-West Passage. 2 Vols. London,. 1908.

40. MacDougal, D. T. Botanical Explorations in the South-west. _Journ. New York Botanical Garden_, Vol. V. p. 89. 1904.

{ Goeppert, H. R. and A. Menge. Die Flora des Bernsteins. 41. { Danzig, 1883. { Conwentz, H. Monographie der baltischen Bernsteinbäume. { Danzig, 1890.

42. Hovelacque, M. Sur la Nature végétale de l'_Aachenosaurus multidens._ _Bull. Soc. Belge de Géol._ etc. Tome IV. p. 59. 1890.

43. Oliver, F. W. and D. H. Scott. On the structure of the Palaeozoic seed _Lagenostoma Lomaxi_. _Phil. Trans. R. Soc._ Vol. CXCVII. p. 193. 1904.

44. Kidston, R. On the fructification of _Neuropteris heterophylla_. _Phil. Trans. Royal Soc. London_, Vol. CXCVII. p. 1.

45. Smith, Geoffrey. A Naturalist in Tasmania. Oxford, 1909.

46. Campbell, D. H. On the Distribution of the Hepaticae, and its significance. _New Phytologist_, Vol. VI. p. 203. 1907.

47. Kidston, R. and D. T. Gwynne-Vaughan. On the Fossil Osmundaceae. Phil. Trans. R. Soc. Edinburgh, Vols. XLV., XLVI. 1907-09.

48. Seward, A. C. Fossil Plants. 2 Vols. Cambridge, 1898-1910.

49. Wallace, A. R. The Malay Archipelago. London, 1886.

50. Reid, C. and Eleanor M. The Lignite of Bovey Tracey. _Phil. Trans. Royal Soc. London_, Vol. 201, p. 161. 1910.

51. Hollick, A. and E. C. Jeffrey. Studies of Cretaceous Coniferous remains from Kreischerville, New York. _Mem. New York Bot. Garden_, Vol. III. 1909.

52. Hutton, F. W. The Lessons of Evolution. London, 1902.

INDEX

_Aachenosaurus multidens_, 68 _Agathis australis_, 107 _A. Moorei_, 108 _A. robusta_, 108, 109 Amber, 65, 66 Amethyst Mountain, 59, 60, 104 Amundsen, E., 62 _Anacharis alsinastrum_, 20 Angiosperms, history of, 16, 53, 69, 70 Annual rings, 5-9 Antarctic fossil plants, 70, 117 _Araucaria Bidwillii_, 115 _A. brasiliana_, 109 _A. Cookii_, 111, 118 _A. excelsa_, 110, 111, 114, 115, 118 _A. imbricata_, 109, 111, 113, 118 Araucarieae, 106-120 Araucarioxylon, 112 _Araucarites Oldhami_, 113 _A. sphaerocarpus_, 116 Arbutus Unedo, 31-33, 36 Archaean rocks, 43 Arctic plants, 22, 23, 30, 69, 127 Arctic-Alpine plants, 22, 23 Arizona, fossil forests of, 59 Artocarpus, 28, 29

Baiera, 129, 131 Banks, Sir Joseph, 110 Barry, forest beds at, 13 Bennett, A., 21 _Bidens tripartita_, 46, 47 Bishop, Mrs, 126 Bommer, C, 73, 82, 89 Bovey Tracey, fossil plants from, 101-103 Bower, Prof., 73 Bracken Fern, 75, 77, 83, 87 Brandon, flint-knappers of, 3 Brigg, dug-out boat from, 10, 11 British flora, 19-38

_Caltha palustris_, 47 Campbell, Prof. D. H., 79 Candolle, A. P. de, 7, 33 Canton, W., 34 Carboniferous plants, 66-68, 72-75, 127 Carruthers, Dr W., 115 Cedars, 27 Cheddar Pink, 24 _Cinnamomum prototypum_, 65, 66 Climate, fossil plants and, 68, 69 Coal age, plants of the, 19, 66, 67 Connemara, 30, 31 Cook, Capt., 111 Coral polyps compared with plants, 8 Cordaites, 112 Cornwall, Pyrenean Heaths in, 31 Cretaceous plants, 16, 17, 53, 82, 117 Cromer Forest bed, 48 _Cryptomeria japonica_, 111 Cycads, 11, 72-74

_Daboecia polifolia_, 30 Dacrydium, 85 Dakota group, flora of, 17 _Dammara alba_, 107 Darwin, C, 16, 24, 25, 33, 39, 40, 61, 133 Devonshire, Pyrenean Heaths in, 31 _Dianthus caesius_, 24 Dipteris, 77, 92-94 _D. conjugata_, 92, 93 _D. Horsfieldii_, 86, 93 Disco Island, Fossil plants from, 28, 69, 82, 103 Discontinuous distribution, 26 Dispersal of plants, rate of, 25, 26 Distribution of plants, 15-38 Drift-wood, 61-63 _Dryas octopetala_, 22 Dufferin, Lord, 61

_Elodea canadensis_, 20, 21 Engler, Prof., 23 _Erica ciliaris_, 31 _E. Mackaii_, 31 _E. mediterranea_, 30, 31 _E. vagans_, 31 _Eriocaulon septangulare_, 35-38 Ettingshausen, Baron, 105, 132

Ferns, 71-94 Flowering plants, see Angiosperms Forbes, E., 31-34, 37 Fossil plants, as thermometers, 68; preservation of, 56-70

Gardner, J. S., 132 Geographical distribution of plants, 15-38 Geological evolution of Britain, 29 Geological record, 39-55 Geological table, 42, 43 Geological time, 2, 3, 49 _Ginkgo biloba_, 113, 120-133 Ginkgoales, 18, 120-133 Ginkgophyllum, 128 Glacial period, effect on vegetation of, 29-32, 45, 47 _Gladiolus illyricus_, 31 Gleichenia, 81-83 Graham's Land, 70, 117 Gunn, Dr Marcus, 117 Gwynne-Vaughan, Prof., 80 Gymnosperms, 17, 18

_Habenaria intacta_, 37 Halifax, plants from canal near, 21 Heer, O.,33, 82, 101 Henry, A., 126 Hirase, Prof., 124, 125 Hofmeister, W. F. B., 125 Hollick, A., 119 Holmes, T. Rice, 2 Hooker, Sir J. D., 4, 15, 16, 22, 23, 27, 40 Hose, C, 87 Huxley, T. H., 11, 52

Ireland, Mediterranean plants in, 30-38

Jeffrey, Prof. E. C, 114, 119 Jet, 114 Juan Fernandez, 84 Jurassic flora, 53, 54, 70, 117 Jussieu, A. de, 109

Kaempfer, E., 121 Kauri Pine, 107 Kidston, Dr E., 74, 80 Knaresborough, petrifying spring at, 64 Krakatau, new flora of, 33, 31

Laccopteris, 90, 91 Lang, Dr A. , 27 Lankester, Sir Edwin Ray, 49 Lhwyd, E., 57 Linnaeus, C, 121, 123 Liriodendron, 28, 29 Liverworts, antiquity of, 79 London Pride, 31 Longevity of trees, 1-10 _Luzula racemosa_, 23 _L. spicata_, 23, 24

MacDougal, Prof., 62 Maiden Hair Tree, 120-133 Mammoth trees of California, 95-105 Man, first appearance of, 49 Marchantia, 79 Market Harborough, Elodea discovered near, 20 Marshall, E. S., 38 Matonia, 77, 86-94 _M. pectinata_, 86-88, 92, 93 _M. sarmentosa_, 87 Matonidium, 89 Mediterranean plants in Ireland, 30-38 Miller, Hugh, 59, 115, 117 Milligan, Dr, 2 Moss, Dr C. E., 23 Mull, Fossil plants in Isle of, 132

_Naias graminea_, 21 Nathorst, A. G., 64, 103, 117 Native plants, 20 New forest, 31 _Nipa fruticans_, 50-52 Nipadites, 50, 52 Norfolk Island Pine, see _Araucaria excelsa_

Oaks, longevity of, 4 Oliver, Prof. F. W., 74 _Osmunda regalis_, 76-79, 83 _Osmundites Dunlopi_, 80

Palaeozoic plants, 55, 66-68, 71, 127, 128 Peat, trees in, 12, 13 Permian floras, 55 Petrifaction, 64-67 _Picea excelsa_, 46, 48 Pines, Tertiary, 65, 66 _Pinus sylvestris_, 11-13, 47 Pipewort, 36-38 Pliny's Natural History, 4 Podocarpus, 109 _Potamogeton pennsylvanicus_, 21 Praeger, E. L., 32, 36, 37 Pre-Glacial plants, 22, 45-48 _Primula elatior_, 24 Protodammara, 119 Psygmophyllum, 127 _Pteridium aquilinum_, 75, 77, 83, 87 Pteridophyta, 18, 124 Pteridosperms, 74, 75 Pyrenean plants in Ireland, 31-38

Ray, John, 56 Reddish Canal, plants from the, 21 Redwoods of California, 95-105 Reid, Clement, 13, 22, 45, 102 Reid, Mrs, 22, 102 Rhaetic plants, 54, 94 Riccia, 79 Ridley, H. N., 25 Royal Fern, 76-79, 83 _Rubus chamaemorus_, 22

St Dabeoc's Heath, 30, 32, 37 _Salisburia adiantifolia_, 122 Saporta, the Marquis of, 70 _Saxifraga oppositifolia_, 22 _S. umbrosa_, 31 Scandinavian plants in Britain, 21-23, 30 Scots Pine, see _Pinus sylvestris_ Scott, Dr D. H., 74 Sequoia, 5, 95-105 _Sequoia Couttsiae_, 101 _S. gigantea_, 5, 95, 96, 98-104 _S. magnifica_, 104 _S. novae zeelandicae_, 105 _S. sempervirens_, 45, 96, 98, 104 Sheppey, fossil plants from, 50, 132 _Shorea leprosula_, 25 _Silene acaulis_, 22 _Sisyrinchium angustifolium_, 38 _S. californicum_, 38 Smith, G., 75 Smith, Sir J. E., 122, 123 Smith, W., 41 Sollas, Prof., 58 _Spiranthes romanzoffiana_, 38 _Stellaria holostea_, 46, 47 Steno, 57 Strahan, A., 13 Strawberry tree, 31, 32

Tansley, A. G., 12, 13, 87 _Taxodium distichum_, 103 Tertiary plants, 31-33, 37, 49, 50, 103 _Theobroma cacao_, 7 _Thyrsopteris elegans_, 84 _Todea barbara_, 11, 78 _T. radicans_, 78 _Trapa natans_, 47, 48 Triassic period, 54, 55 Tulip tree, 28

Walchia, 113 Wallace, Dr A. R., 85 Wealden flora, 17, 53 Weismann, A., 3 Wexford, American plant from, 38 Williamson, Prof. W. C, 72 Wilson, E. H., 120 Winchester Cathedral, wood from foundations of, 10 Woodward, Dr J., 57 Woodworthia, 114

Yellowstone Park, fossil trees in the, 59-61, 104

Zeiller, R., 113

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GENERAL EDITORS P. GILES, Litt.D. Master of Emmanuel College and A. C. SEWARD, M.A., F.R.S. Professor of Botany in the University of Cambridge

VOLUMES NOW READY

The Coming of Evolution. By Prof. J. W. Judd, C.B., F.R.S. Heredity in the Light of Recent Research. By L. Doncaster, M.A. The English Puritans. By the Rev. John Brown, D.D. The Idea of God in Early Religions. By Dr F. B. Jevons. Plant-Animals: a Study in Symbiosis. By Prof. F. W. Keeble, Sc.D. Cash and Credit. By D. A. Barker, I.C.S. The Natural History of Coal. By E. A. Newell Arber, M.A. The Early Religious Poetry of the Hebrews. By the Rev. E. G. King, D.D. The History of the English Bible. By the Rev. John Brown, D.D. Plant-Life on Land. By Prof. F. O. Bower, Sc.D., F.R.S. An Historical Account of the Rise and Development of Presbyterianism in Scotland. By the Rt Hon. the Lord Balfour of Burleigh, K.T., G.C.M.G. English Dialects from the Eighth Century to the Present Day. By the Rev. Prof. W. W. Skeat, Litt.D., D.C.L., F.B.A. The Administration of Justice in Criminal Matters (in England and Wales). By G. Glover Alexander, M.A., LL.M. An Introduction to Experimental Psychology. By Dr C. S. Myers. The Ground Plan of the English Parish Church. By A. Hamilton Thompson, M.A., F.S.A. The Historical Growth of the English Parish Church. By A. Hamilton Thompson, M.A., F.S.A. Aerial Locomotion. By E. H. Harper, M.A., and Allan E. Ferguson, B.Sc. Electricity in Locomotion. By A. G. Whyte, B.Sc. New Zealand. By the Hon. Sir Robert Stout, K.C.M.G., LL.D., and J. Logan Stout, LL.B. (N.Z.). King Arthur in History and Legend. By Prof. W. Lewis Jones, M.A. The Early Religious Poetry of Persia. By the Rev. Prof. J. Hope Moulton, D.D., D.Theol. (Berlin). Greek Tragedy. By J. T. Sheppard, M.A. The Wanderings of Peoples. By Dr A. C. Haddon, F.R.S. Links with the Past in the Plant-World. By Prof. A. C. Seward, F.R.S. Primitive Animals. By Geoffrey Smith, M.A. Life in the Sea. By James Johnstone, B.Sc. The Moral Life and Moral Worth. By Prof. Sorley, Litt.D., F.B.A. The Migration of Birds. By T. A. Coward. Earthworms and their Allies. By F. E. Beddard, M.A., F.R.S. Prehistoric Man. By Dr W. L. H. Duckworth. The Modern Locomotive. By C. Edgar Allen, A.M.I.Mech.E. The Natural History of Clay. By Alfred B. Searle.

VOLUMES IN PREPARATION

Ancient Assyria. By Rev. C. H. W. Johns, Litt.D. The Civilisation of Ancient Mexico. By Lewis Spence. Clouds. By C. T. R. Wilson. F.R.S. The Work of Rain and Rivers. By the Rev. Prof. T. G. Bonney, LL.D., Sc.D., F.R.S. Rocks and their Origin. By Prof. Grenville A. J. Cole. The Measurement of Time, By the Astronomer Royal. St Paul and Christianity. By the Rev. Principal Headlam, D.D. The Development of Coinage. By George Macdonald, LL.D. The Origin of Earthquakes. By Dr C. Davison. A History of Civilisation in Palestine. By Prof. R. A. S. Macalister, M.A., F.S.A. Glaciers and Ice Sheets. By Prof. Garwood, M.A., Sec.G.S. Goethe in the Twentieth Century. By Prof. J. G. Robertson, M.A., Ph.D. The Psychology of Insanity. By Dr Bernard Hart. The New Field Botany. By Dr C. E. Moss. Spiders. By C. Warburton, M.A. Flies. By Dr Gordon Hewitt. The Green Leaf. By Dr F. F. Blackman, F.R.S. The Phoenicians. By Prof. J. L. Myres, F.S.A. The Physical Basis of Music. By A. Wood, M.A. The Meteorology of the Globe. By Dr W. N. Shaw, F.R.S. Brewing. By A. Chaston Chapman, F.I.C. The Talmud. By I. Abrahams, M.A. Growth and Form. By Prof. D'Arcy W. Thompson, C.B., M.A. Beyond the Atom. By Prof. J. Cox. The Early History of India. By E. J. Rapson, M.A. Methodism. By Rev. H. B. Workman, D.Lit. The Ballad in Literature. By T. F. Henderson. Life in the Medieval University. By R. S. Rait, M.A. The Icelandic Sagas. By W. A. Craigie, LL D. Mysticism in Modern English Literature. By Miss C. F. E. Spurgeon. The Early Religious Poetry of India. By A. A. Macdonell. German School Education. By K. H. Breul, Litt.D. The Moral and Political Ideas of Plato. By A. M. Adam, M.A. The Growth of Municipalities. By H. D. Hazeltine, M.A Ancient Babylonia. By Rev. C. H. W. Johns, Litt.D. Early Christian Poetry. By F. C. Burkitt, M.A.. F.B.A. Discovery in Greek Lands. By F. H. Marshall, M.A. The Poetry of Burns. By H. J. C. Grierson, M.A. The Crusades. By Rev. Prof. J. P. Whitney, B.D.

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Transcriber Note

Illustrations were repositioned to avoid splitting paragraphs. The errata note was applied to the text.