493 



P. with an oblong, oval, thick fhell, of a dull brown 

 colour, ftrongly reticulated ; feme of the longitudinal 

 ridges are much coarfer than the reft, and are frequently 

 tuberculated by the croffing of the tranfverfe ftrise : ver- 

 tex not much elevated, truncated, and furnillied with an 

 oblong perforation. Infide fmooth, white, fometimes 

 rayed with dull purple or brown; margin not even, but 

 fomewhat indented or arcuated at the fides, and finely 

 crenated. Length about three-quarters of an inch ; 

 breadth fcarce half an inch ; height a quarter. 



This fhell is rarely found of a fuperior fize on the En- 

 glijli coaft, but foreign fpecimens are fometimes an inch 

 and a half in length. It has generally been confidered as a 

 rare fpecies in this country : Da Costa fpeaks of it from 

 Weymouth, and obferves, that he never could learn that 

 they inhabit any other Britijh coaft. 



Do61or PuLTENEY alfo mentions it from the fame 

 place, and from Poole. We have found it on Stud^ 

 land beach in Dorfefjliire, larger than ufual. Is rare in 

 Cornwall ; but on fome parts of the fouth coaft. of Z)<?t;ore 

 not uncommon, efpecially on Milton fands : and fre- 

 quently dredged up alive in Salcomb bay, but feldom 

 exceeding half an inch in length. It is not unufual on 

 Sandwich flats in Kent, as we have been allured by Mr. 

 Boys. Dead fl-.ells are mod commonly of a pale-brown, 

 or yellowilh-white, and fometimes ilreaked, or fpotted 

 with dark-brown. 



GEN. 



