10 BUDS AND STIPULES 



but in the genera above mentioned the number is 

 indefinite more than can come to maturity ; and yet the 

 rudiments, which are constructed to produce true leaves, 

 cannot modify themselves into bud-scales. Thus, in the 

 Ash, Maple, Horse Chestnut, and Oak, which have true 

 terminal buds, there are comparatively few leaves ; 

 while in the Elm there are about seven, Hornbeam 

 eight, Lime eight, Willow fifteen,, and Lilac fifteen. 



In the above species it is generally the uppermost 

 lateral bud or buds which develop, but in some cases, as 

 in Viburnum Opulus (the Guelder Rose), Gymnoclad/>is, 

 &c, these also perish, and as a rule only the lower ones 

 grow, and the upper part of the stem dies back. 



The arrangement of the leaf in the bud influences, 

 and sometimes determines, the form of the leaf. 



This consideration explains, I think, the curious 

 fact that the first leaves, or cotyledons, often, indeed 

 generally, differ altogether in shape from the true 

 leaves. They offer an immense variety of form ; not 

 quite so innumerable, indeed, as those of true leaves, of 

 which Linnaeus truly observed ' that ' Natura in nulla 

 parte magis fuit polymorph a quam in foliis,' but still 

 immense. They may be large or small, broad or 

 narrow, entire or much divided. 



Now, why should the first leaves differ so much 

 from their successors ? The reason, I believe, is that 

 while the forms of leaves often depend greatly on the 

 1 Philosophia Botanica. 



