184 



GEMMARIA. 



GEMMARIA McCr. 



Gemmaria McCr. Gymn. Charl. Harbor, p. 49. 

 Zanclea McCr. (non Geg.). Gymn. Charl. Harbor, p. 48. 

 Zanclea Aga^s. {p. p.). Cent. Nat. Hist. U. S., IV. p. 344. 1862. 

 Acrochordium Mey. ; in Nov. Ac. N. Aur XVI. 1834. Hydrarium ? 



Gemmaria gemmosa McCr. 



Gemmaria gemmosa McCr. Gymn. Charl. Harbor, p. 49, PI. 8, Figs. 4, 5. 



Zanclea gemmosa McCr. Gymn. Charl. Harbor, p. 49. 



Zanclea gemmosa Agass. Cont. Nat. Hist. U. S., IV. p. 344. 18G2. 



McCrady has distinguished with reason the genus Gemmaria from 

 Fig. 306. the Zanclea of Gegenbaur. The form 



of the bell of the digestive cavity and 

 of the tentacles are totally different in 

 the two genera. Very young specimens 

 (Fig. 306) of this species, observed at 

 Naushon, differed essentially from the 

 Geynmaria cladophora of Massachusetts 

 Bay, in the character of the tentacles 

 and the shape of the clusters of lasso- 

 cells ; in the present species, the clus- 

 ters of lasso-cells are attached by a short 

 peduncle, and are arrow-shaped ; the 

 great tenuity of the bell in the speci- 

 men here figured is a characteristic of the younger stages, which dis- 

 appears in older specimens. (See McCrady's figures.) 



Charleston, S. C. (McCrady) ; Buzzard's Bay, Naushon (A. Agassiz). 



Gemmaria cladophora A. Agass. 



The shape of the inner bell of the adult Medusa of this species is 

 peculiar ; the outline does not follow that of the outer bell (Fig. 307), 



Fig. 306. Profile view of halt of a young Gemmaria gemmosa ; magnified. 

 Fig. 307. Profile view of Gemmaria cladophora; magnified. 



