142 PATELLA. LIMPET. 



indented, and toothed : length about three quarters of an 

 inch ; breadth half an inch ; height a quarter. 

 Western coasts, and Dublin bay. v. m. 



19. Patella Zetlandica. Shetland Limpet. 

 JEdinlurg Encyclopaedia, viii. p. 66. no. 17. 



Shell oblong, conic, glossy white, transparent, furnished 

 from the point to the margin with numerous equal tubercled 

 ribs : crown much raised, nearly straight and central, trun- 

 cate, not in the least curved, with an oval perforation which 

 is beaded round the edge by the tubercled ribs 3 the base 

 nearly round, undulate or beaded; inside glossy white: 

 length hardly a line ; height as much. 



This beautiful minute species, which was first described, 

 we believe, by Dr. Leach, as having been found among 

 some small shells from Shetland, was discovered by Mr. 

 Tardy, in the fine drifted sand from Portmarnock, in Dub- 

 lin bay : it differs from the last, in being as long as it is 

 broad, and in having both the base and the crown beaded 

 round the circumference, v. m. 



20. Patella Nubecula. Red-rayed Limpet. Fig. 81. 

 Lister, pi. 529. 



Shell oblong-oval, sometimes a little contracted in the, 

 ihiddle, semitransparent, a little convex, white with red or 

 nrownish-red rays which are broader or narrower, some- 

 times interrupted, and often not extending quite to the 

 crown, with numerous obscure longitudinal ribs, and a few 

 irregular transverse furrows which give it a rather rugged 

 appearance towards the margin : crown not quite central, 

 with an oblong perforation, round which is often a purplish 

 ring ; inside white, glossy, with a purplish ring round the 

 perforation at the bottom ; the margin plain : length five 

 eighths of an inch ; breadth and height about three- 

 eighths. 



These shells have been frequently brought to us, as 

 having been dredged off the Land's End, on the Cornish 

 coast; but it has not occurred to us, as yet, to find them 

 ourselves, v. m. 



PHOLAS, 



