LAMELLARIA. 357 



animal is " oval, retklish or brownish, sometimes nearly 

 white. The upper part of the body is very convex, 

 covered with a thick, tough ligamentous skin, that conceals 

 the shell and extends downwards on each side, where the 

 edges are thin and detached from the body. On the fore- 

 part of this margin is a sinus, through which the animal 

 protrudes an appendage or arm, somewhat flat, a quarter 

 of an inch in length, the extremity of which is bifid ; the 

 lower division terminating in a thread-like process. The 

 body of the animal beneath, or rather the sustentaculum, is 

 oblong and flat, with a deep depression between it and the 

 marginal skin ; the head is furnished with two small white 

 tentacula, at the base of which are two small black eyes. 

 It is possessed of considerable locomotive powers, and when 

 in motion frequently contracts the margin or loose skin 

 into wrinkles, or folds, exposing the sides of the body. It 

 is in size three times as large as its shell, and is incapable 

 of much contraction or expansion." The specimen we 

 have figured was taken on the west coast of Ireland, and 

 was nearly white. It was slightly pustulated on the back. 

 It appears to range throughout the British seas but 

 very sparingly, inhabiting the laminarian zone and the 

 belt of nullipore. Montagu had it from Devon and Dorset. 

 Exmouth (Clark) ; Tenby (Lyons) ; Isle of Man, in 

 eighteen fathoms (E. F.); Skye (M'Andrew and E. F.) ; 

 Scarborough (Bean) ; in shallow water, Northumberland 

 (Alder) ; in seven fathoms, Dudgeon, alive on fuci in 

 Kirkwell Bay, and in fifteen fathoms, Eda Sound, Orkney 

 (Thomas) ; Loch Carron (Jeftreys) ; on both sides of the 

 Irish coast, sparingly (Thompson) ; Dublin Bay (Hassall) ; 

 Bantry Bay (Jeffi-eys). 



