DICORYNE CONFERTA. 293 



DicoRTNE CONFERTA, Alder. 



Plate VIII. 



EuDENDRiuM ? coNFERTUM, — Alder, Catal., p. 13, pi. i, figs. 5 — 8. 



DicoRYNE STRICTA, — Allman, in Ann. Nat. Hist, for Nov., 1859. 



DicoRYNE CONFERTA, — Allman, in Ann. Nat. Hist, for August, 1801. Althr, Suppl. 



Catal., p. 4, pi. viii, figs. 1, 2. Hincks,Zv\\,. llydr. Zooph., 



p. 105, pi. xviii, fig. 1. 



TROPHOSOME. — Htdrocaulus composed of much-branched stems, which attain 

 a height of about half an incli, with usually some short simple ones, all crowded on a 

 creeping, closely reticulated hydeorhiza ; branches subalternate, ascending at a very 

 acute angle from the stem ; perisauc continued as a cup-like expansion for a very 

 short distance over the base of the hydranth, marked by transverse though rather 

 indistinct corrugations towards the hydrorhizal extremity of the stem. Htdrantii 

 with about sixteen tentacles alternately elevated and depressed in extension. 



GONOSOME. — Blastostiles claviform, borne on the extremities of cylindrical 

 stalks, which are covered with a perisarc, and spring, some from the main stem and its 

 branches, others directly from the hydrorhiza. Gonophores oviform on short 

 peduncles, densely clustered round the blastostyle ; planoblast, with its two diverging 

 tentacles, nearly equalling in length the rest of the zooid. 



Colour. — Perisarc opaque earthy brown; hydranths ash-bvovvn. 

 Development of Gonosome. — Summer and autumn. 

 Habitat. — Investing the shells of Buccinmn and of other Gasteropoda. 

 Bathpiietrical Bisfribtition. — Larainarian and Coralline zones. 



Localities. — Orkney Islands and Firth of Forth, G. J. A. Shetland Islands, Rev. A. M. 

 Norman. Coast of Northumberland, Mr. Alder. 



Some years ago I dredged from a depth of about three fathoms in the Orkney Seas an old 

 Buccinum shell which was invested with a moss-like covering due to a hydroid which proved on 

 examination to possess characters which excluded it from every previously defined genus. I 

 accordingly assumed it as the type of a new genus, and named it Dicoryne sfricta. 



The same hydroid, however, had been previously described by ]\lr. Alder as a Eudendriiun 

 under the name of Eudendriuw confertum, though with some doubt as to the correctness oi' 

 referring it to this genus ; and as his description was drawn up from imperfect specimens, no 

 gonosome having been developed in them, I had overlooked the identity of his hydroid with 

 mine. There can, however, as Mr. Alder afterwai'ds ascertained, be no doubt of this identity, 



