THE PRODUCTION OF GRAFTED EMBRYOS. 85 



The blastulae are particularly interesting for they make it 

 possible to determine definitely whether the component members 

 of a cluster are merely agglutinated or fused. Figs. 26, 27 and 



36 37 38 



43 

 FIGS. 36-43. 



28 represent half blastomeres in varying degrees of approximation 

 or separation, with their blastocceles entirely separate. Figs. 



29 and 30 represent an agglutination of a half and a whole egg, 



