144 BRITISH TUXICATA. 



29. (?) Ascidia orbicularis Midler. 



Ascidia orbicularis MULLER Zool. Danica, II [1788], p. 53, 

 pi. Ixxix, figs. I, '2; THOMSON in Ann. Nat. Hist. (1) V 

 [1840], p. 94; FORBES and HANLEY Brit. Moll. I [1848], 

 p. 34; THOMPSON Nat. Hist. Ireland, IV [1856], p. 360. 



II oil i/ orbicular, depressed, whitish, adhering through- 

 out. Aperture* nearly terminal, approximated, sessile. 

 Text hyaline, transparent, spreading, having small, 

 unequal tubercles. Mantle opaque white or reddish 

 with yellow lines. 



Diaritrfrr an inch. 



Hal. Shallow water, on sea-weeds. 



IRELAND. -"Strangf or d Lough, Down, on Zostem 

 mo riii a ( Tli o i i ipson) . 



First record.- -Thompson [1840]. 



30. (?) Ascidia vitrea Van Beneden. 



Ascidia i-itrca VAN BENEDEN Recli. Ascidies simples, in 

 Mem. Acad. Roy. Belg. XX [1847] , p. 61, pi. iv, figs. 1-5 ; 

 FORBES and HANLEY Brit. Moll. I [1848], p. 34; ALDER 

 and HANCOCK in Trans. Tyneside N. F. Club, I [1848], p. 

 200; [FORBES in Rep. Brit. Assoc. 1850 (1851), p. 242; 

 MERRIFIELD Nat. Hist, Brighton (1860), p. 81]. 



Body sub-globose or ovate, a little compressed. 

 Apertures terminal, placed a little apart, the branchial 

 largest and most produced, but both short ; ocelli red. 

 Test thin, transparent, membranous, and colourless. 

 Mantle white, with a yellow ring near the branchial 

 aperture. 



Lentjth half an inch. 



Hub. Shallow water, on sea-weeds, &c. 



ENGLAND. Cullercoats, Northmnb., on small sea- 

 weeds (Aldi'-r). [Brighton, Sussex (Merrifield, 186')). 

 Falmouth, Cornwall (Cocks, 1849).] 



IRELAND. Killery Bay, Galway, on an Alcyonidium 

 (Ball, Thompson, and Forbes). 



First record. Forbes, 1848; coll. 1840. 



