238 



liarities of the resulting segmeutatioii, with which Born is chiefly 

 concerned, we have nothing to do. The dorsal lip of the blastopore 

 appears at one edge of the egg, but the blastopore closes near the 

 opposite edge, the dorsal lip apparently migrating over the yolk. 

 The neural folds make their appearance on the under side of the egg. 

 Altogether the conditions are strikingly like those of the abnormally 

 situated pricked egg above described. And as in that case, it way 

 be that here too, some simple mechanical explanation, connected with 

 the varying pressure against the glass of dorsal and ventral lips, 

 may account for the abnormal position of the egg. 



University of North Carolina, Chapel Hill N.C., U.S.A., 

 June 12, 1900. 



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