SEPARATE CENTERS 



OF ORGANIZATION 



COMMON AMNIOTIC 

 VESICLE 



TUBE- LIKE C AN AL 



SE PAR AT E EMBRYOS 



SEPARATE CENTERS 



OF ORGANIZATION 



CENTER OF 

 ORGANIZATION 



Fig 186 Polyembryony or the development of multiple embryos m the armadillo, 

 Tatusia novemcincta. (After Patterson, '13.) (A) Separate centers of organization in 

 the early blastocyst. (B) Later stage in development of multiple embryos. Each embryo 

 is connected with a common amniotic vesicle. (C) Section through organization centers 

 a and b in (A). The two centers of organization are indicated by thickenings at right 

 and left. (D) Later development of four embryos, the normal procedure from one 

 fertilized egg in this species. 



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