384 CONSERVATIVE ORGANS. [LECT. VII [. 



that of the axillary bud ; and this may be done 

 most readily in the succulent shoot of any tree or 

 shrub in early spring, as, for example, of the 

 common Lilac, which is at this time (March 26th) 

 just expanding its leaves. 



In the shoot now under consideration, one 

 inch only in length, and on which none of the 

 real leaves, except the three first pairs, are yet 

 expanded, we cannot perceive, on pulling off 

 those nearest the base, that is, the intermediate 

 between the scales of the bud from within 

 which the shoot has protruded and the real 

 leaves-}", any appearance of a bud in their axillae, 

 even when the sight is aided by a good lens : 

 neither is any seen at the attachments of the 

 second pair. At the third, however, we observe 

 by the aid of the lens, immediately above the la- 

 ceration produced by tearing off the leaf, a mi- 

 nute elevation, resembling a semitransparent 

 vesicle depressed in the centre ; which, under the 

 microscope, appears to be a lobular body, with 

 a small green speck in the central depression (see 

 Plate 7, fig. 1, a) %. This is the rudiment of the 



f The distinguishing characteristics of real leaves, and of 

 those which appear first on a new shoot, shall be pointed out 

 when we examine the external structure of buds. 



J In this figure, which represents a thin tangental slice of 

 the shoot very highly magnified, a. displays the appearance of 

 the embryon germ within the bud ; and b. the lacerated base of 

 the footstalk of the removed leaf: c. is the natural size of the 



