5IO The Trees of Great Britain and Ireland 



Twigs slender, glabrous, or with slight pubescence near the tip only ; stipule-scars 

 absent. Leaf-scars small, crescentic, set somewhat obliquely on slightly prominent 

 pulvini, surrounded by a narrow raised rim, marked with three bundle dots. Buds 

 conical, pubescent, and acute ; scales five or six, imbricated, pubescent, ciliate, reddish 

 or greenish ; terminal bud larger than the lateral buds which arise at an angle of 

 about 45. Pith solid, but interrupted by transverse woody partitions, showing on 

 longitudinal section a ladder-like appearance. 



The inner scales of the bud are accrescent ; and the base of the shoot is marked 

 by ring-like scars, indicating where these scales have fallen off in the preceding 

 spring. 



Varieties 



This species is extremely variable in leaf, both in wild specimens and cultivated 

 trees. This is well shown in the Strathfieldsaye tree, the leaves of which vary 

 from a long elliptical acuminate to a short broad obovate obtuse outline ; some are 

 quite glabrous, whilst others are pubescent on the midrib and principal veins beneath. 

 Usually the leaves are very shining above and coriaceous ; but in a tree growing at 

 Kew in a wood, they are dull above and thin in texture. In some specimens there 

 are numerous glands on the under surface of the leaf; whilst in others, as in a 

 specimen growing in the Arnold Arboretum collected by Elwes, no glands are visible. 

 The fruit is also variable, being either terete or flattened. The tree occurs in 

 America in very diverse stations, both on wet soils and on dry mountain slopes ; and 

 this may explain the remarkable extent of its variation. 



Van biflora, Sargent, Silva N. Anier. v. 76, t. 218 (1893). 



Nyssa biflora, Walter, Fl. Carol. 253 (1788); Loudon, Arb. et Frut. iii. 131 7 

 (1838); Sargent, Trees N. Amer. 709 (1905). 



Leaves smaller than in the type, very narrow, glabrous and glandular beneath, 

 quite entire in margin. Fruit with an oval, flattened stone, narrowed at both ends 

 and prominently ribbed. This variety is a small tree, rarely more than 30 feet high, 

 growing in ponds on the pine barrens near the coast from N. Carolina to Louisiana. 

 It usually has a trunk with a swollen base, and appears to be a form of the species 

 which has adapted itself to life in water. 



The cultivated trees mentioned by Loudon as being Nyssa biflora were all 

 probably Nyssa sylvatica of the typical form. (A. H.) 



Distribution 



Nyssa sylvatica is found in North America from Southern Ontario, where it 

 grows to a good size near Niagara, and in New England, where I saw it in the 

 neighbourhood of Boston 60 or 70 feet high, westwards to Central Michigan and 

 South-Eastern Missouri, and southwards to Florida and Texas. It attains its largest 

 size, according to Sargent, in the southern Appalachian Mountains, growing as high as 

 100 feet with a maximum girth of about 15 feet.' It is found generally in wet soil on 



' But Ridgway measured a black gum in Wabash Valley, 125 feet high by 13 feet in girth, and 64 feet to the first limb. 



