ARTIFICIAL PARTHENOGENESIS IN ANNELIDS 677 
developed from one egg; No. 2 shows two trochophores which 
are grown together but are otherwise independent. In No.3 
we notice the beginning of a common organization, inasmuch 
as the clear peripheral areas (on the right side) are fused 
together. In Nos. 4, 5, and 6 the clear areas are almost com- 
FIG, 161 
pletely fused together, and only the dark centers remain 
separated. In No. 7 both eggs are fused completely and 
form one giant embryo with one set of organs. Cases like 
this are very frequent in the material treated with KCl. 
Nos. 8 and 9 are examples of the fusion of more than two 
eggs. I have seen four eggs form one giant embryo with one 
common dark center and one common clear area. Such mon- 
sters swam, but usually died sooner than the single embryos. 
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