210 PHILOSOPHICAL NOTES ON 



leaves, instead of occurring in the same plane as the blade of the 

 leaf, occur in different planes, like the leaves of a branch." He 

 adds, " thus shoeing the close relationship, if not the intrinsic 

 identity^ between the leaf-stalk and its continuation the midrib, 

 with the branch and its sub-divisions'' He also states that Casimir 

 de Candolle propounded the notion that " the leaf is the equivalent 

 of a branch, in which the upper portion of the vascular circle is 

 abortive."* 



In another place I have stated that, from observations made in 

 India, I had come to the conclusion that the leaf was only a 

 repetition, on a small scale, of the branch, very much as the bud- 

 scale is a repetition, on a still smaller scale, of the leaf, and the 

 hair, on a microscopical scale, a repetition of the bud-scale. 



Also, in discussing the genesis of the axillary bud, I have 

 endeavoured to show that it is a branchlet of the leaf which 

 corresponds to a cladophyl ; that when the leaf decays, or before, 

 this branchlet (axillary bud) takes the lead and continues the 

 growth of the plant. 



Now if we look upon the plumule of the seed as a bud, we 

 immediately perceive that the cotyledon or cotyledons naturally 

 take their place as either stipules or bud-scales, the plumule, in 

 lengthening, corresponding to the petiole of the leaf. 



Indeed, we have only to gknce at a section of a grain of 

 wheat, given in Fig. 66, to be convinced that the corm-like part 



Fig. 66. Grains of Wheat, " Henslow's Bot. for Beginners " : (a) cotyledon 

 and embryo, (6) back and front view of the same. 



of the seed, containing the starch and gluten, is no other than a 

 thickened bud-scale, which we have styled cotyledon, and that the 

 embryo or bud occupies its axilla. 



* "Theorie de la feuille " (Arch, des Sc. Bibliot^que Universelle, 1868). 



