516 THE INFLUENCE OF MUTILATION ON THE FORM OF PLANTS. 



smooth. The leaves on the suckers of the Round-eared Willow (Salix aurita) 

 are broadly ovate, fairly smooth, and the veins in the blade form a wide-meshed 

 reticulum; the leaves on non-mutilated branches are widened in the upper third, 

 strongly wrinkled, and covered with grey hairs, whilst the reticulum of the veins 

 is narrow-meshed. In Salix rosinarinifolia, the leaves of the suckers are twice 

 or three times as broad as those of the normal branches, and they are smooth, 

 while those of ordinary branches are covered with silky hairs, and gleam like 

 silver. Hundreds of trees and shrubs might be mentioned in which there is a 

 distinct difference between the foliage of the suckers and of the normal branches 

 of the crown. But these few examples will suffice, and we will only mention 

 the Norway Maple {Acer ijlatanoides), because the difference in the foliage-leaves 

 can be seen from the illustrations in vol. i. The leaves of the summit (see vol. i. 

 fig. 106, p. 416, and fig. 109, p. 419) are borne on long petioles, the blade is 5-7 

 lobed, and the lobes are short and beset with several pointed, tapering teeth. 

 The leaves of the suckers in this same Norway Maple are short-stalked, the blade 

 is slightly 3-lobed, and each lobe is triangular and without the elongated pointed 

 teeth. They exactly resemble the first foliage-leaves shown in vol. i. p. 9, fig. 1 ^ 

 This is also true of the leaves on the suckers of other woody plants. The shoots 

 developed from reserve buds, " eyes ", and the like, repeat to a certain extent the 

 beginning of the leafy stem, so that the phenomenon is only an exhibition of the 

 usual metamorphosis of the foliage-leaves. The difference between the older and 

 younger, i.e. lower and upper foliage-leaves, only seems strange because the two 

 kinds of leaf-forms are not usually seen simultaneously on one and the same 

 plant. By the time the crown of a tree has developed, the first (oldest) leaves 

 which adorned the young sapling have long disappeared. Many descriptive 

 Botanists, as a rule, only consider the foliage-leaves of the fully -grown trees 

 and bu.shes; some of them have hardly ever seen the first leaves of the commonest 

 trees, and when they do happen to come across them they regard them as an 

 extraordinary phenomenon, declare the shoots bearing them to be " bud variations ", 

 and draw bold and bewildering hypotheses from their appearance. This alteration 

 in form, however, has nothing to do with the formation of varieties, nor is it 

 dependent either upon the influence of the soil or upon the effect of climate. 

 Moreover, the form of leaf characteristic of the sucker is not possessed by the 

 secondary shoots which arise from the suckers; these are adorned with the same 

 foliage which occurs on the topmost branches of the tree. 



Alterations in the scale-leaves as well as in the foliage are brought about by 

 mutilation of the In-anches. When the upper portions of Willow boughs with 

 their foliage-buds are cut off, leaving the lower portions with the buds of the 

 flower-catkins on them, the small pale scales at the base of the catkins change 

 into green foliage-leaves; the axis bearing these leaves elongates, and the catkins 

 then form the termination of a leafy shoot. Many Willows, e.g. Salix cinerea 

 and S. grandifolia, by this metamorphosis assume a very unusual appearance. 

 In the following year the branches bearing the flower -catkins, if they are 



