EUDENDRIUM. 159 



all over the stem, resembling in this respect very strikingly the Peri- 

 gonimus of Sars, to which the Hydrarium also bears a close affinity, 

 from the size of its sterile Polypes. 



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



Cat. No. 43, Naushon, Mass., Sept. 1861, A. Agassiz. Hydrarium. 



Cat. No. 437, Naushon, Mass., 1864, A. Agassiz. Medusa. 



EUDENDRIUM Ehrenb. 



Eudendrium Ehrenb. Corall. d. Roth. Meeres. 1834. 

 Eudendrium Agass. Cont. Nat. Hist. U. S., IV. p. 342. 1862. 

 Calamella Oken. Lehrb. der Naturg. Gesoh. 181."). 

 Thoa Lamx. Pol. Cor. Flex. 1816. 



Eudendrium dispar Agass. 



Eudendrium dispar Agass. Cont. Nat. Hist. U. S., IV. pp. 285, 289, 342, Fig. 36 ; PI. 27, Figs. 



10-21. 1862. 

 Thoa dispar Agass. Cont. Nat. Hist. U. S., IV. PI. 27, Figs. 10-16. 1862. 



This Hydroid (Fig. 249) is closely allied to the J^^;^*^' 



Tubularia ramea of Dalyell and the Coryne pu- 

 silla var. muscoides of Johnston. The male and 

 female communities are readily recognized by the 

 different color of the Medusse buds ; the male Me- 

 dusae buds are bright orange, while the females 

 are of a dull pink. 



Massachusetts Bay (Agassiz). 



Cat. No. 34, Nahant, Mass., Sept. 1854, H. J. Clark. Hydrarium. 



Cat. No. 35, Suisconset, Mass., July, 1849, L. Agassiz. Hydrarium. 



Cat. No. 36, Nahant, July, 1861, A. Agassiz. Hydrarium. 



Cat. No. 37, Nahant, July 11, 1861, A. Agassiz. 



Cat. No. 38, Naushon, Mass., September, 1861, A. Agassiz. 



Cat. No. 405, Nahant, June, 1862, A. Agassiz. Hydromedusarium. 



Cat. No. 423, Eastport, Me., A. E. Verrill. 



Museum Diagram No. 23. 



Fig. 249. Female Medusse buds in different stages of development. 



