410 THE AMERICAN NATURALIST. 
EXPLANATION OF PLATE II. 
Ic. 1. Egg in first cleavage phase; ?,a protoplasmic band connecting the 
blastomeres. 
IG. 2. A second phase of cleavage, indicated by furrow cutting off a small 
blastomere at x. Two protoplasmic strands are shown, one, 7, the same as in 
Fig. 1 
Fic. 3. Next phase ten minutes later. 
Fics. 4-6. Show successive phases in progress of the development. 
IGS. 7-11. Show phases of cleavage in another egg, which differ in some 
respects from the former, yet resulting in practically same condition 
