GENERATION AND DEVELOPMENT 



699 



ife, and, small as it is, it contains all that is necessary for multiply- 

 ing and producing its kind, in this respect differing in no essential 

 particular from the larger organism of which it is only a microscopic 

 atom. 



All cells, somatic or germ, consist of cell-contents and cell-wall. 

 The contents are colloidal in character, structureless, and are 



Fig. 244-- 



-DlAGRAM ILLUSTRATING THE PROCESS OF CELL DIVISION 

 (AFTER BOVERI). 



generally described as protoplasm or cytoplasm. Within the cell 

 and lying in the cytoplasm is another and smaller cell, known as 

 the nucleus. The nucleus consists of cell-wall and cell-contents, 

 but the latter are not structureless. The nucleus of all cells is an 



