TRANSACTIONS OF THE SECTIONS. 91 



ing old univalve shells, and having much the habit of a Hydractinia. — E. capillare, 

 a minute slender-branched species, having the polypes and reproductive capsules on 

 different branches. — Sertularia tricuspidata, somewhat resembling S. polyzonias, 

 but more nearly allied to a New Zealand species (S. Johnstoni, Gray). It has three- 

 toothed apertures to the cells. — Sertularia tenella, a species supposed by Dr. John- 

 ston to be a variety of S. rugosa with the habit of S. polyzonias, but it differs from both 

 in some of its characters. — Campanidaria volulilis, C. Johnstoni, and C. Hincksii. 

 The Linnean species is re-described for the purpose of distinguishing it from the 

 other two, which have been confounded with it. According to the opinion of the 

 author, the C. volubilis of Johnston differs from that of Ellis. The latter is considered 

 to be the Linnean type, and the second species is named C Johnstoni. They differ 

 in the form of their ovicapsules, as well as in other particulars. A third species, 

 ■with the margin of the cell sculptured in a castellated form, had been previously ob- 

 served by the Rev. T. Hincks, and is here called C. Hincksii. — C. gracillima, a 

 species allied to C. dumosa. — Grammaria, a genus lately described by Mr. Stimpson 

 in 'A Synopsis of the Marine Invertebrata of Grand Manan,' published by the Smith- 

 sonian Institution of Washington. The British species, now first noticed, comes 

 very near to the G. rohtista of Stimpson, but differs in being much branched. It is 

 called G. ramosa. — Bushia, a new genus of Polyzoa, belonging to the family Vesi- 

 culariadse. It is parasitical, and consists of small cells, closely adhering to other 

 substances, with marginal spines also adhering. They are united by a creeping fibre. 

 The species B. nitens is minute, shining, and horn-coloured. — Farrella pedicellata. 

 Found on old shells from deep water. It differs from the Laguncula {Farrella) elon- 

 gata of Van Beneden in the great length and slenderness of the pedicle, and in some 

 other respects. — Alcyonidiiim mammillatum, an encrusting species, found on old 

 shells, distinguished by the size of the papillae. — A. albidum, enveloping the stem of 

 Plumularia falcata with prominent whitish polypides. 



A skull of a Manatee, obtained by Dr. Baikie in Africa, was exhibited to the 

 Section. 



Dr. Ball, of Dublin, exhibited a Dredge which he had found of the greatest use 

 in making dredging excursions. 



Notice of a new Crustacean, Monimia Whiteana. By Spence Bate, Plymouth. 



Observations on the Acalephce, with respect to Organs of Circulation and Respi- 

 ration. By Professor J. H. Corbett, M.JD., Queen's College, Cork, 



In this communication the author claimed for the Acalephse a degree of organi- 

 zation higher than that usually conceded to them, and which might be supposed 

 consistent with so soft and perishable a structure. He described two different sets of 

 vessels— a centrifugal and centripetal ; the former divide, subdivide, and anastomose, 

 as they proceed towards the circumference of the disc ; the latter larger, but less in 

 number, commence towards the circumference and pass in straight lines towards 

 the centre, where they become connected with the plaited red bands which are 

 disposed around the gastric cavity. It seems evident that the tubes which circulate 

 the nutritive fluid are not simply gastro vascular canals as generally described, but 

 really vessels which assist in maintaining a complete circulation. The four bands 

 situated around the gastric cavity are considered by recent authors as exclusively 

 the organs of reproduction, consisting of vesicles which contain sperm-cells in the 

 male and ova in the female. The contributor of this paper believes these to be 

 compound parts, and states that the vascular plaited bands are organized in an 

 appropriate manner for carrying on the respiratory action, while the contained 

 vesicles are the agents of the reproductive function. According to some writers, 

 respiration is accomplished by the agency of the cilia, which are attached along the 

 margin of the disc ; but as ciliary appendages are frequently absent amongst the 

 Medusae, such a view cannot be considered as satisfactory. 



The following considerations seem to indicate that the membranous constituents 

 of these bands are branchial or respiratory organs :— 1st, by their position around 



