•294 Z. ASCIDIOIDA. Acamahchis. 



from the collection of the late Dr Walker, which he received from 

 Miss Blackburne from the coast of Cheshire," Fleming. " Found 

 in Dublin Bay and Belfast Lough," Templeton. 



" Height several inches, dichotomously divided, spreading ; the 

 cells are narrow, rather diverging, and more than the half of the outer 

 summit is free ; the pearly helmet-shaped ovaria opening transversely, 

 were at one time considered by Ellis as the young of Neritae." Flem- 

 ing. 



2. A. PLUMOSA, cells linear-oblong^ with a spine at the outer 

 and upper angle ; the aperture elliptical, entire. Doody. 



Plate xxxix. 



Corallina pumila erecta ramosior, Raii, Syn. i. 37, no- 20, tab. 2, fig. 1. 

 Ellis, in Phil. Trans, abridg. x. 346, pi. 8, fig. h, B-B Soft feather- 

 ed coralline, Ellis, Corall. 33, no. I, pi. 18, fig. a, A Sertularia 



fastigiata, Lin. Syst. 1314. Fabric. Faun. Grcenl. 445. Turt. Gmel. 

 iv. 684. Berk. Syn. i. 219. Turt. Brit Faun. 216. Wern. Mem. i. 



565. Stew. Elem. ii. 448 Cellularia plumosa. Pall. Elench. 66. 



Hogg's Stock. 35 C. fastigiata, Blumenh. Man. 273. Flem. Brit. 



Anim. 539 Cellaria plumosa, Ellis and Soland. Zooph. 21. Bosc, 



Vers, iii. 131. Lam. Anim. s. Vert. ii. 140. 2de edit. ii. 190. Crisia 



plumosa, Corall. 62 C. fastigiata, Templeton in Mag. Nat. Hist. ix. 



468 La Bicellaire plumeuse, Blainv. Actinolog. 459. 



Hah. " Not uncommon beyond low water-mark," Fleming. Leith 

 shore, Jameson. In deep water at Scarborough, common, Mr Bean. 

 Eare in Berwick Bay, G. J. " Common on the coast" of Ireland, 

 Templeton. 



Polypidom attached by fibrous roots, subcalcareous, caulescent, 

 erect, from 2 to 4 inches high, very much branched, the branches 

 panicled, dichotomous, with linear or filiform segments ; cells oblong 

 with a short pointed spine on the superior outer angle, smooth, pel- 

 lucid or somewhat crystalline, marked always with a black or orange- 

 coloured dot near the centre, the remains of the dried polype ; ovaries 

 pearly, globular or pear-shaped, placed over the apertures. 



In habit this fine species is sometimes like Sertularia argentea, but 

 in general it is more tufted and bushy. Specimens occur without 

 an ovary on any cell, while others are loaded with them ; and in one 

 of the latter sort I found some of the segments of the branches com- 

 posed of a triple series of cells. The whole polypidom is often co- 

 loured of a pink or pui'plish hue. In an old condition the cells be- 

 come obsolete, and the habit of the species so altered, as to render 

 its detection in this guise somewhat difficult to the inexperienced. 

 Dr Fleming does not adopt this genus, which Blainville is also of 



4 



