92 A. J. GOLDFARB. 



79 and 80. The archenteron in such fusions may grow beyond 

 the boundaries of the blastomere or egg into the blastoccele of its 

 neighbor as seen in Fig. 81. In the second group the archentera 



67 



are usually atypic either- detached as in Fig. 82 or independent, 

 Figs. 83 and 84. 



