294 Transactions. — Zoology. 





Art. XLIII. — Description of a new Crustacean, Phronima novse-zealandise. 



By LI. Powell, M.D. 



Plate XXI. 



{Read before the Philosophical Institute of Canterbury, 15th September, 1874.] 



The little Crustacean I am about to describe belongs to a small family of 

 amphipodous Crustacea which are particularly interesting on account of their 

 habit of what I venture to call eremitism. They are found almost invariably 

 inhabiting the cavities of the tests of certain tunicate mollusks, and what have 



been described as Beroidse. One described specimen, however, was found in 

 the stomach of a shark, but whether inhabiting this curious residence from 

 choice or necessity I do not know. Dr. Haast entrusted this specimen to me, 

 Mr. A. E. Ross having found it on the Sumner beach, and presented it to the 

 Museum, and I much regret that I have not the opportunity of showing the 

 Phronima alive in its little crystal palace, but the small quantity of sea-water 

 was unfortunately poured away, and we were obliged to transfer it to spirits. 



The Phronima is about seven-eighths of an inch long when extended \ it is 

 as transparent as glass, the eyes alone being coloured red, and was contained in 

 a little cask-shaped body, open at both ends, the openings being slightly 

 contracted, one somewhat smaller than the other, composed of a perfectly 

 transparent semi-cartilaginous substance. It is about three quarters of an inch 

 in length, and half an inch in diameter, irregularly quadrangular, one of the 



;ed, the whole being wrinkled transversely. It is the test 

 of a tunicate mollusk, probably one of the Salpidse. A very similar structure 

 associated with another Phronima, found in the Mediterranean, P. sedentaria, 

 is figured in the British Museum Catalogue of Amphipoda under the name of 

 Doliolum papillosum, Delia Chiaje. Our specimen, however, is not papillose 

 and differs in form. 



The Phronima was doubled up in its cell facing one of the openings, and 



win 



be 



immediately clambered back again. 



found 



West 



ANDI^E 



Cephalon very large, tumid above, tapering to the oral apparatus, finely 



masrn 



pellucid dots. Antennse as long as the breadth of the cephalon at their 



insertion, the first ioint bein 



First pair of gnathopoda having the meros slightly produced posfcero 



