The Biological Record 321 



as well as its germ- form. In each the new individual begins 

 existence as a single microscopic egg cell or germ cell, which 

 in one case is the complete creature, while in the other it 

 divides and sub-divides repeatedly, to build up its structure, 

 patterned after that of its ancestors, and so regenerates a 

 complete creature. 



It is not surprising that when this marvellous fact was 

 ascertained, it was supposed that the primary unit of 

 organized life was seen. The cell was so hailed. Yet now, 

 in a little time, it appears that the cell itself is not primary, 

 but is a complex organization. It has parts, and these parts 

 have separate functions. It has structure and history, and 

 heredity, within its tiny wall, not only for itself, but for 

 the complex individual creature, which its egg substance is 

 to breed. And so we look again for the elemental unit. 

 And as yet we do not find it; but must seek it by paths 

 indicated by analogy, inference, aspiration, desire. Mean- 

 time we study the still imperfectly known cell, which is 

 marvellous enough to arrest attention, and to constitute a 

 real point of departure, from which new views are possible. 

 It is in fact in these new views, that this present era of 

 hfe study is founded. 



The scheme of nature, as revealed in the organization of 

 the cell, is emphatically evolutionary. Heredity in all its 

 complex completeness is contained in the substances and 

 functions of a single cell ; or, when sexual duality is in 

 view, in two half cells of similar species. Whatever appears 

 in the young elaborated physique of a highly specialized 

 creature, came to it through the mechanism and chemistry 

 of a cell. That it was compounded of two parents, and so 



