POLLICIPES CORNUCOPIA. 299 



Coast of Portugal; mouth of the Tagus. England,* Ireland, and the 

 Frith of Forth in Scotland. Mediterranean (according to Brugiere) : 

 Teneriffe : Mogador, Africa. 



Capitulum, obtusely triangular, massive : valves close 

 together, rather thick, with their exterior surfaces convex, 

 naked, except in the lower parts, where united together 

 by tough, greenish-brown membrane, destitute of spines. 

 The edges of the orifice are widely bordered by mem- 

 brane, coloured fine crimson red. The valves, in a spe- 

 cimen with a capitulum above three quarters of an inch 

 long, were 52 in number; in a specimen one fifth of an 

 inch long, only between 20 and 30. Two whorls of 

 valves are distinct beneath the carina and rostrum. In 

 one specimen in Mr. Cuming's collection, with a capitulum 

 1*4 of an inch long, there were three whorls beneath 

 the rostrum, and four beneath the carina. The scuta, 

 terga, and carina are much larger than the other valves. 



Scuta, oval, the basal and t ergo-lateral margins sweep- 

 ing into each other, and the apex pointed ; internally 

 (PI. VII, fig. ] a) the pit for the adductor muscle is deep. 



Terga, larger than the scuta, internally (fig. 1 a) slightly 

 concave ; carinal margin much curved and protuberant ; 

 basal angle blunt ; scutal margin either curved with the 

 upper part straight, or formed of two almost distinct 

 lines, corresponding with the tergal margin of the scutum, 

 and with one of the sides of the upper latus. 



Carina, much curved, extending far up between the 

 terga, internally deeply concave, widening much from the 

 top to the bottom ; basal margin highly protuberant, with 

 a central portion either truncated and very slightly hol- 

 lowed out, or bluntly and rectangularly pointed, with the 

 apex itself rounded. 



Rostrum, not one third of the length of the carina, 

 concave, triangular, with the basal margin slightly pro- 



* This species is said by Montagu (' Test. Brit. Supplement ') to have 

 been found attached to drift timber in the Frith of Forth, and to the bottom 

 of a wrecked vessel towed into Dartmouth. According to Mr. W. Thompson 

 ('Annals of Nat. Hist.' vol. xiii, p. 436), it has been found attached to wood- 

 work near Dublin. 



