IV] 



THE SECOND GRADE 



103 



Fig. 7. Gonium. A, a species containing 16 cells embedded in a flat 

 ' plate of gelatinous substance. B F, another species, containing 

 4 cells. J3, C, adult colonies, seen from the top and side re- 

 spectively. In D one, in E two, and in F all four cells have 

 divided into four. The four groups of four cells in F will shortly 

 separate and become independent daughter-colonies. (Highly 

 magnified.) (From West.) 



