GERM CELLS OF HERMAPHRODITES 199 
elements is explained by Ancel by supposing the 
transformation of the cells into sex cells to cease 
Fic. 58.— Helix arbustorum. Stages in the differentiation of male and 
female sex cells. A. Nucleus of germinal epithelium. B. Nucleus 
of nurse cell. C. Nucleus of indifferent sex cell. D. Spermatogo- 
nium of first order. EH. Spermatogonium of second order. F. Grow- 
ing odcyte. (From Buresch, 1911.) 
before nurse cells are formed; thus all the sex cells 
would become spermatogonia. 
More recently Buresch (1911) has repeated the 
