122 Z. HYDROIDA. Sektularia. 



tuw opposite rotos, sessile, distinct and separated by a joint from 

 the stem, short icith everted apertures : vesicles scattered. — Po- 

 lypes hydraform. 



* Cells distinctly alternate. 

 1. S. PoLYZONiAS, erect, subjlexuous ; cells ovate, with a 

 wide somewhat uneven aperture ; vesicles obovate, wririkled across^ 

 the orifice contracted and plain. Mr Newton, 

 Plate VIII. Fig. 1, 2, 3. 

 Corallina minus ramosa, alterna vice denticiilata, Raii, Syn. 35, no. 13, 



tab. 2, fig. 4, male Great Tooth Coralline, Ellis, Coral. 5, no. 3, 



pi. 2, fig. a, A. and pi. 38, fig. 1, A. Sertularia polyzonias, Lin. 



Syst. 1312. Ellis and Soland. Zooph. 37. Berk. Syn. i. 219. Turt. 

 Gmel. iv. 683. Blumenb. Man. 273. Turt. Brit. Faun. 216. Wern. 

 Mem. i. 564. Stew. Elem. ii. 447. Lam. Anim. s. Vert. ii. 117. 2de 

 edit, ii 142. Lamour. Cor. Flex. 190. Corallina, 83. Risso, L'Europ. 

 merid. v. 130. Bosc, Vers, iii. 119. Hogg's Stockton, 31. Flejn. 

 Brit. Anim. 542. Johnston in Trans. Newc. Soc. ii. 256. Templeton 



in Mag. Nat. Hist ix. 468 S. ericoides, Pall. Elench. 127 Ser- 



tolara polizonia, Cavol. Polip. Mar. 224, tav. 8, fig. 12-14 La Ser- 



tulaire zonee, Blainv. Actinolog. 480. 

 Hah. On shells and other corallines, in deep water. Near Queen- 

 borough in the island of Sheppey, Ellis. Leith shore, Jameson. 

 Coast of Ayrshire, Mr P. W. Maclagan. On the shore of Belfast 

 Lough, Templeton. Cork Harbour, J. V. Thompson. Scarborough, 

 Mr Bean. Coasts of N. Durham and Berwickshire. — (/3.) Corn- 

 wall, Pallas. Isle of Wight, Ellis. Berwickshire. 



Polypidoms affixed by a creeping tubular fibre, from 1 to 2 inches 

 high, of a yellowish horn-colour, filiform and slender, scarcely zig- 

 zag, simple or sparingly branched in general, but specimens occasion- 

 ally occur which are bifariously pinnated ; the pinnae alternate, erec- 

 to-patent. Cells rather distant with an oblique joint in the stem 

 above the origin of each of them, urceolate, smooth, the aperture wide 

 and obsoletely tridentate. Polypes white or sometimes bright-yel- 

 low, with numerous tentacula. Vesicles large, sessile, ovate with a 

 short tiibulous apex, smooth or transversely wrinkled on the upper 

 half. 



Pallas describes a variety (/3) worthy of notice, not unfrequent 

 on the coast of Cornwall, 3 inches and upwards in height, with 

 a compound stem, and branched in a pinnate manner similar to Thoa 

 halecina, which this variety indeed very closely resembles. Ellis 

 mentions that he had received specimens of the same from the Isle of 

 Wight ; and I have found it on the coast of Berwickshire. In the col- 

 lection of my friend Dr Coldstream there are specimens also, from 



