KEPRODUCTION BY BUDDING. 



495 



rather than through that thickened and stronger place. The phenomena 

 are equally well accounted for by imputing the first action to the utricle 

 itself, which, exerting a constrictive pressure upon the endochrome in the 

 direction of one of the great circles of the cell, divides it in the manner 

 that we see. 



This process of multiplication is exhibited in Fig. 231, in Conferva 



Fig. 231. 



Cell reproduction in Conferva glomerata. 



glomerata, which consists of a system of cells arranged in a filament. At 

 A two states are shown, complete partition at , and incomplete at a / at 

 B, C, D, the successive steps of partition, a being the primordial utricle, 

 b the endochrome, c cell membrane, d mucous investment. At E the 

 primordial utricles are separated, and the cell membrane intervenes. At 

 F the membrane is completed so as to exhibit lamina. 



The cells which have thus arisen by subdivision soon grow to the 

 size of the one from which they were derived, and are ready for subdi- 

 vision in their turn. Indeed, it often happens that traces of incipient 

 subdivision may be detected long before the cell has reached its mature 

 dimensions. 



The reproduction of cells by budding may be illustrated by the vesi- 

 cles of the yeast-plant ; and though, in those cases in which the budding 

 cell possesses a nucleus, the nucleus is not necessarily involved, yet the 

 conclusion indicated in the preceding paragraph is greatly strengthened, 

 for we must clearly attribute the result which now takes place to an in- 

 creased nutrition of the primordial utricle upon a restricted portion of 

 its surface, and not to a distention arising from a pressure of the endo- 

 chrome within. So closely does this resemble the preceding mode of re- 

 production, that they are commonly said to be really of the same kind, 

 or, rather, to offer no other distinction than this, that in the former the 



