42 



beaks to the anterior angle of the anteal margin ; 

 hinge straight, with the teeth fine, and numerous 

 posteally, and large and few anteally ; inner margin 

 denticulated. Epidermis brown, fringing the margin. 



Dimensions of the largest specimen : L. -^j^ ; B. 1. 



Animal with the foot thick, rose-colour ; the man- 

 tle white, with short filaments. Foot in one speci- 

 men furnished with a horny process or operculum, 

 adapted to the gape of the shell. 



I dredged two living specimens of this fine species 

 in twenty fathoms water, off the coast of Ballaugh, 

 in September 1835. They were found imbedded in 

 the mud filling the cavities of dead Modiol^e. Dr. 

 Turton first noticed the species as British ; the loca- 

 lity he gives is " the Calves, west of Ireland."'' See 

 British Bivalves, p. 169, t. 13, fig. 1. 



LXI. Pectunculus, Lam. 

 1. pilosus. 



Pectunculus pilosus, La77i. — Area pilosa, Li7i, 

 — Area glycimeris, Peiin. 



a, Pectunculus pilosus, Turt. 



j8. Pectunculus glycimeris, Turt. (not 



of Lin.) 

 y. Pectunculus undatus, Turt. 

 Animal cream-white, margin of foot even. 

 Comm.on in deep water on all the coasts ; especially 

 abundant off Douglas Head. The varieties a, /3, and 

 7, are found together, and are probably only the same 

 species in different stages of growth. Is not the 

 Pectunculus decussatus of Turton, the young of P. 



