630 UEV. O. HENSLOW ON VEBNATION AND FOLIAGE 



the back, i. e. the underside of the leaf. The Beech differs from 

 the Lime in having its young leaves dependent only and not pro- 

 tected. They are feebly conduplicate, but with a plicate surface, 

 and the stipules do not form any protection ; and, contrary to 

 what takes place in the Lime, the older, basal leaves, instead of 

 covering the younger ones, hang below them, the slender shoot 

 curving at the apex so that the terminal and younger leaves have 

 a tendency to be vertical, but not to so pronounced an extent as 

 in the Lime. It may be noticed that the Beech does not open its 

 buds till a later period than the Lime, and at a time when spring 

 frosts are nearly over. The Spanish Chestnut agrees closely with 

 the Beech, the leaves being at first subconduplicate, and similarly 

 plicate, while each leaf on expansion is spread out below the 

 terminal shoot. Both trees belong to the same section of tbe 

 Cupulifera?. 



II. Compound Leaves. (1) Opposite : (i) erect. — The Ash 

 and the Elder are illustrations. As with simple leaves, the leaf- 

 lets of compound leaves are almost invariably conduplicate ; the 

 Elder, however, as stated above, having the margins of the leaflets 

 involute as well. They all stand erect at first and only gradually 

 assume the horizontal position on their complete development. 

 The leaflets of the Ash are at first similarly clustered together, 

 but simply conduplicate. With Weeping Ashes, in order to place 

 the young leaves erect, the petiole is obliged to make a very strong 

 curve upwards, not necessitated in the ordinary form of the tree. 



(ii) pendulous. I have not met with an instance of opposite 

 compound leaves being pendulous in the young state. 



(2) Alternate : (i) erect. — Of compound leaves there are the 

 two types, digitate and pinnate. Of the former, Lupin will 

 illustrate this position. A specimen with white flowers had the 

 leaflets all conduplicate at first and erect, forming a small but 

 dense mass. Of the pinnate type with erect leaflets many instances 

 might be mentioned, as, e. g., Goutweed, Chervil, Sumac, Rasp- 

 berry, and Eose. As a rule, besides being conduplicate and, 

 in some cases, plicate in addition, the leaflets are all pressed 

 together laterally, thereby affording a certain amount of mutual 

 protection. This is well seen in the Rose. 



In the case of the Eose the developing bud is protected by the 

 adnate stipules (fig. 7), and the young leaf, when it merges, is at 

 first erect (as in the Pea, figs. 8 and 9). The leaflets are condu- 

 plicate and all five pressed together laterally ; for at this stage 



