354 HYDROID^. Part IV. 



Clytia Lam.v. — CxAicQWix HincJcs. — Trochopyxis yly. — Hydra: a Cam- 

 panularia of the type of C. volubilis. 



C. volubilis Lamx. See p. 297. — Northern Europe (Lamouroux). 



C. bicophora Ag. See p. 304. — Ifassac/mseits Bay (Agassiz). 



Campanularia noliformis McCr., PL 11, fig. 4, from Charleston, South 

 Carolina, — Campanularia Gegenbauri Sars; Gegenb., Generat., PI. 

 1, fig. 1, from Messina, — and Campanularia Johnstoni Hincks ; 

 Wright, Ed. Phil. Journ., 1858, Vol. VII. PI. 7, fig. 3, from 

 the British shores, belong also to this genus. 

 Platypyxis Ag. See p. 306. 



PI. cylindrica Ag., PI. 27, figs. 8 and 9. — 3Iassachusetts Bag, Nahant 

 (Agassiz) ; BuzmnVs Bag, Naushoa (A. Agassiz). 



Thaumantias octona Forties, PI. 9, fig. 2, Tartjct, Scotland, — T. qua- 

 drata Forbes, PI. 9, fig. 2, Tarhet, — T. aeronautica Forl)es, PI. 9, 

 fig. 3, Brassag, Zetland, — T. maculata Forbes, PI. 9, fig. 4, Zet- 

 land, — T. globosa Forbes, PI. 10, fig. 4, Zetland, — T. melanops 

 Forbes, PI. 10, fig. 3, Zetland, — and Eucope thaumantoides 

 Gegenb., PI. 9, fig. 9, Messina; E. campanulata Gegenb., PI. 9, 

 fig. 8, Mess-ina; E. aflfinis Gegenb., PI. 9, fig. 12, Messina, which 

 are, probably, the males and females of the same species, at 

 different stages of growth, belong either to this genus or to 

 the preceding and following genera. 



Geryonia planata Will, PI. 2, figs. 13 and 14, Trieste (Will), belongs 



also to this family, and may be the type of a distinct genus, 



if its eyes really alternate with the tentacles, as Will's figure 



and description indicate. 



Wrightia Ag} — Hydra: a Campanularia of the type of C. Syringa. 



W. Syringa Ag. — Sertulai'ia Syringa Lin. — Northern Europe (Lin- 

 naeus). To this genus belong also the Laomedea acuminata 

 Alder; Wright, Ed. Phil. Jour., 1858, Vol. VII. PL 1, and 

 the Laomedea lacerata Wright, Ed. Phil. Jour., 1859, Vol. IX. 

 PL 3. Some of Forbes' species of Medusae, quoted above, 

 may, perhaps, belong to this genus rather than to Platypyxis. 



' The genus Wriglitia differs from Clytia proper to this, the Hydra of -which has only ten tentacles. 



in having the eyes near the tentacles, instead of Campanulata verticillata and Hincksii belong also 



occupying the middle of the space between them. to distinct genera, for the first of which the name 



"We have an undescribed species upon the shores Campanularia may be retained. I shall describe 



of Massachusetts, and another genus closely allied their American representatives on another occasion. 



