Ginkgo 57 



Jacquin ^ grafted on the male tree at Vienna, when it was quite small, a bud of 

 the female tree, from which a branch developed. This tree is now of large size ; and 

 numerous branches regularly bear male flowers, whilst one branch, now very stout, 

 bears female flowers. This female branch puts forth its foliage about fourteen days 

 later than the male branches, and retains them much later in autumn. In this case 

 the shoot retains its individual characters, and the stock does not affect it even in 

 regard to its annual development. 



Seedling. The germination in Ginkgo is not unlike that of the oak. We are 

 indebted to Mr. Lyon^ of Minneapolis for figures of the seedling, which are repro- 

 duced on Plate 1 5 c, d. 



When the seeds are sown the hard shell is cracked at its micropylar end by the 

 swelling of the embryo within. Through this opening the body of the embryo is 

 thrust out by the elongation of the cotyledons; which remain attached to the caulicle 

 by two arching petioles ; between these the plumule or young stem ascends, while the 

 root turns down into the soil. The cotyledons remain attached throughout the first 

 season's growth. The first two or three leaves directly above the cotyledons remain 

 small and scale-like. After reaching 4 or 5 inches in height the stem stops growing, 

 having expanded into a rather close crown of ordinary leaves at its apex, which ends 

 in a large terminal bud. The root attains in the first season about the same length 

 as the stem, and develops numerous lateral fibres. This primary root, as is usually 

 the case in Gymnosperms, persists as the tap-root of the plant. 



Sexes. Certain differences, besides those of the flowers, are observable in 

 male and female trees.^ The male trees are pyramidal and upright in habit, the 

 ascending branches being of free and vigorous growth. The female trees are closer 

 and more compact in habit, more richly branched below, and the branches sometime 

 become even pendent.* 



Monsieur L. Henry * states that in Paris the leaves of the female Ginkgo fell three 

 or four weeks later than those of the male. Generally male trees are completely 

 denuded of foliage by the beginning of November, while the female trees retain 

 their leaves till the end of November or the beginning of December. 



Burrs. In Japan there often develops on old Ginkgo trees peculiar burrs, 

 which are called chi-chi or nipples. These may be observed in an incipient stage on 

 the large tree at Kew. They occur on the lower side of the larger branches of the 

 tree, and vary in size from a few inches in length to 6 feet long by i foot in diameter. 

 They occur singly or in clusters, and are generally elongated, conical in shape, with a 

 rounded tip. If they reach the ground, as is sometimes the case, they take root, and 

 then bear leaves. They are due to the abnormal development of dormant or adven- 

 titious buds. A description of this curious phenomenon and a photograph of a tree 

 bearing a large number of these growths is given by Fujii in Tokyo Bat. Mag. 



' Kerner, Nat. Hist, of Plants (Eng. trans.) ii. 572. 

 ^ See Lyon's paper in Minnesota Botanical Studies, 1904, p. 275. 



' Sargent denies this, and says it is impossible to distinguish the sexes till the trees flower ; but observations on the 

 Continent go to show that the sexual differences pointed out above really exist. See Sargent, Garden and Forest, 1890, p. 549. 

 * See Schneider, Dendrologische Winterstudien, 127 (1903), and Max Leichtlin in Woods and Forests, Jan. i6, 1884. 

 ' Bull, de r Assoc, des anc. ilhi. de Ficole d'Hort. de Versailles, 1898, p. 597, quoted in Card. Chron. 1899, xxv. 201. 



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