308 ALLEN. [VOL. I. 



find any trace of eggs, and that the embryos are developed 

 from a large spherical portion which buds off from a granular 

 mass of protoplasm formed by the separation of the endoderm 

 and ectoderm in the medusoid bud. This granular mass he 

 calls the "germ basis." A study of stained specimens in sec- 

 tion shows clearly that this granular mass, or "germ basis," as 

 he calls it, is really the mass of sex cells which have already 

 been described. His opinion that the embryo was formed by 

 the budding off of large portions of this mass probably arose 

 from the fact that in the early stages of the development the 

 eggs are packed closely together and the membranes are indis- 

 tinct, so that the whole mass appears somewhat homogeneous. 

 As the eggs grow, they become less granular and in time are 

 entirely separated from the germ tissue. As to the radial 

 canals, they would probably be overlooked, except in sections, 

 as they are never functional. The tentacles of the embryo are, 

 however, so well developed that it seems strange that he should 

 not have observed them, since he has noted tentacles upon the 

 female gonophore where they are less clearly defined. 



SYRACUSE UNIVERSITY, May, 1900. 



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