■ ■■■' 



\, 



: .-:■' 



■%L. 









ect pi. 



- 



f30 ' 7 .1. \ I . 



v. enL 



pr. em 



03L 



ex ict. 



V. cnt 



pr c 



pr. emb. ent. 



Fig. 10 Two egg cylinders of the albino rat found within the same decidual 

 crypt, with in part common ectoplacental cone. X 150. Rat No. S7, 9 days 

 after the beginning of insemination, ect.pl., ectoplacental cone or Trager; 

 p. ert., parietal or transitory ectoderm; v.ent., visceral entoderm; ex.ect., extra- 

 embryonic ectoderm; pr.c, proamniotic cavity; pr.emb.ect., primary embryonic 

 ectoderm; pr. emb. ent., primary embryonic entoderm; mes., mesoderm. 



137 



