32 ASCIDIAD^. 



fast. First distinguished as an Irish species by Dr. J. L. Drum- 

 mond," W. Thompson, Ann. Nat. Hist. vol. v. 1840. Bay of 

 KiUery, Connemara, W. T., R. Ball, E. F. (1840). Hebrides, R. 

 M'Audrew and E. F. (1845.) 



4. A. MENTULA, O. F. Miiller. 



Zool. Dan. t. 8, f. 1-4 (copied in Enc, Meth. pi. 62, f. 2-4).— Ascidia mona- 

 chus, Cuvier, Mem, du Mus, t. ii. p. 32. — Phallusia monachus, Savigny, Mem, 

 pt. 2, p. 167, pi, 10, f. 2. — Pandocia conchilega and Phallusia mentula, Fleming, 

 Brit, An, p. 468. ? — Ascidia prunum, Macgillivray, Mol. Ab. p. 312. ? 

 Plate C, fig. 1. 



Body oblong. Outer tunic very thick, cartilaginous, translu- 

 cent, varying in colour from pale greenish-white to dark brown ; 

 [often containing imbedded Modiola marmorata, and frequently 

 covered by investing corallines,] Orifices distinct, sessile ; the 

 branchial terminal, 8-lobed; the indentations of the lobes pre- 

 senting the ocelli, which are yellow, with a red central spot ; the 

 tentacular filaments are very conspicuous between the ocelli, as 

 they are also in the 6-lobed and G-ocellated anal orifice, which is 

 placed laterally at a considerable distance from the branchial, and 

 usually on a bulging of the side. Grows to the length of six 

 inches, and even longer. This is the commonest of our deep- 

 water Ascidians, occurring plentifully in from fifteen to twenty 

 fathoms water in many parts of the coast, Miillor's description of 

 his A. mentula applies so well to it, that, although the figure be 

 rather puzzling, and not good at best, one can hardly doubt their 

 identity; " Ascidiarum singularissima. Massu informis cinereo- 

 flavescens, quadratum irregulare sistens; substantia crassa gela- 

 tinosa, duriuscula, subpellucida, rejectamentis corallinarum et 

 fucorum passim obsita." 



" Belfast Bay ; Roundstone Bay, County Galway, adhering to a 

 stone between tide-marks (? if the same); Ascidia communis, 

 Forbes' MSS,, Clew Bay," W. Thompson, in Ann, Nat. Hist., 

 1844. Isle of Man, Zetland, Orkney, east and west coasts of 

 Scotland, E. F, 



5. A. ARACHNoiDEA, E. Forbcs, 



Oblong, resembling the last in form. Outer tunic very thick, 

 cartilaginous, hard, smooth, undulated as if obsoletely tuberculated. 



