308 LIVERPOOL MARINE BIOLOGY COMMITTEE REPORT. 



others have merely a sandy investment ; they all, however, 

 seem to belong to the one species, Kupffer's Molgula 

 occulta.'^^ This species has been previously found off the 

 coast of Denmark (Kupffer), at Arendal in Norway (Kupffer), 

 on the coast of Greenland (see Traustedtt), in the Adriatic 

 (Hellert), and at Torbay§ on the English coast. I have 

 recently seen some specimens of the same species which 

 were dredged last summer by Professor Haddon in Bantry 

 Bay, on the S. W. coast of Ireland. 



The Manx specimens vary in size from 0*5 cm. to 3 cm. 

 in extreme length ; they are of the usual more or less ovate 

 shape. In the case of one specimen dredged off Bradda 

 Head, near Port Erin, on August 22nd, from a depth of 

 fifteen fathoms, several large colonies of the Hydroid Clytia 

 johnstoni were found to be attached to the branchial and 

 atrial siphons. When the Ascidian retracted, and the 

 siphons disappeared under the surrounding sandy test, the 

 Zoophytes were crowded together, and to a certain extent 

 drawn in with the siphons, but this compulsory retraction 

 did not seem to have affected the healthy development of the 

 Zoophytes in the least. Probably it was more than compen- 

 sated for by the abundant food supply brought within reach 

 of the zooids by the Ascidian's inhalent and exhalent 

 currents. 



The branchial sac in the Isle of Man specimens agrees 

 in all respects with the descriptions given by Kupffer, 

 Heller, and Traustedt ; the tentacles, however, appear to be 

 usually six large (A), six of median size (B), and twelve small 



* Kupffer, Jahresberichte der Kommission zur Untersuchung der deutschen 

 Meere in Kiel, Berlin, 1874, vii, Tunicata, p. 224. 



f Oversigt over de fra Danmark og dels nordlige Bilande kjendte Ascidice 

 Simplices^ Kjobenhavn, 1880, p. 427. 



X Untersuch. ii. d. Tunicaten d. Adriat.u. Mittelm. iii, Abth. Wien, 1877. 



§ Sorby and Herdman, Journ. Linn. Soc. Loud., Zool., vol. xvi, p. 533, 

 1882. 



