298 Rev. T. Hincks on new British Hydroida. 



much branched ; main stems very slightly fiexuous, of a deep 

 horn-colour below, becoming white and very delicate towards 

 the upper extremity, strongly annulated at the base and above 

 each division, giving off branches at each bend ; branches erect, 

 flexuous, very tender and hyaline, sometimes of great length 

 and much ramified, ringed above every calycle and ramule. 

 Hydrotheca alternate, much elongated, slender, of very thin 

 texture, with nearly parallel sides for two- thirds of the length, 

 and then tapering off to the base, borne on ringed pedicels, the 

 rim cut into numerous shallow denticles of castellated form, 

 slightly indented at the top. Gonothecce axillary, irregularly 

 ovate, flattened at the top, and supported on a ringed stalk. 



Height about 2 inches. 



I place this fine species provisionally in the genus Gonothyraa. 

 From the structure of the capsule I infer that this is its true 

 position ; but I have not traced the history of its reproduction. 



Hah. Profusely investing Tubularia, Halecium, &c., from 

 Shetland. I am indebted to J. Gwyn Jeffreys, Esq., for my 

 specimens. 



CuspiDELLA, nov. gcn. 



Hydrothecse cylindrical or subcylindrical, sessile on a delicate 

 creeping stolon, with a conical operculum, composed of many 

 pieces. Polypites cylindrical, with a single verticil of filiform 

 tentacles. Keproduction unknown. 



C. humilis, n. sp. 



Hydrotheca very minute, subcylindrical, the upper portion 

 divided into ten or twelve convergent segments, which form an 

 operculum. Gonothecce. unknown. 



The calycles of this curious species are little cylinders, termi- 

 nating in a point above, and rising directly and without any 

 trace of a pedicle from the creeping stolon. 



Hah. On the stems of zoophytes : North Wales, Yorkshire, 

 Northumberland, Shetland, Conneniara, 



Suborder SERTULARIDA. 



Family Sertularids. 



Genus Sertularia. 



/Si, uttenuata, n. sp. 



Syn. Sertularia rosacea, Ellis, Corall. 9, pi. 4, fig. C ; Johnston, Brit. 

 Zooph. 470. (Specimen from Orkney, Lieut. Thomas.) 

 Sertularia pinaster, var., Johnston, Brit. Zooph. 72, figs, c, d. 



Hydrocaulus straight, somewhat rigid, pinnately branched, often 

 running out above into long tendril-like filaments, thickened 



