Fic. 49.— Stages in the keimbahn of copepods. A-G. Cyclops fuscus 
var. distinctus. H. Diaptomus ceruleus. I. Cyclops viridis. 
A. Ectosomes at end of first cleavage spindle. B. Two-cell stage; 
ectosomes dissolving. C. Old and newly formed ectosomes at end 
of one of second cleavage spindles. D. Eight-cell stage; ectosomes 
dissolving in stem-cell. £. Sixteen- to twenty-éight-cell stage. 
S=cell with, HE =cell without, granules. F. One hundred and 
twelve-cell stage with two primordial germ cells (vw) and three en- 
toderm cells (#).. G. Two hundred and forty-cell stage. wu = pri- 
mordial germ cells. H. Appearance of ectosomes before cleavage 
spindle forms. J. Increased production of ectosomes due to car- 
bonic acid gas. (From Amma, 1911.) (166) 
