PATELLA-PATINA. 109 



The dentition is said by Dall to be tbe same as Patella except 

 that the third or outer cusp of the third lateral tooth is obsolete. 



The shell is cap-shaped, scaly-ribbed, the apex strongly curving 

 forward. 



P. PECTIXATA Born. PI. 51, figs. 1, 2, 3. 



Shell solid, oval, elevated, cap-shaped, the apex curved forward, 

 nearly to or over the anterior margin. Surface sculptured with 

 numerous close, densely prickle-scaled riblets, alternately larger and 

 smaller. Riblets black, the intervals buff or pinkish. 



Interior of a dull lead color, sometimes a little iridescent at the 

 edge. Length 27, breadth 22, alt. 14 mill. 



Cape of Good Hope. 



Patella pedinata BORX, Mus. Cses. Yindob. p. 423, t. 18, f. 7, 

 (1780). LAM., An. s. Vert, vi, p. 334. POT. & MICH., Galerie, i, 

 p. 529, t. 37, f. 11, 12. KRAUSS, Die Siidafric Moll. p. 57. Not 

 Patella pedinata Lixx., Syst. Nat. x, p. 783, nor of GMELIX, Syst. 

 xiii, =8iphonaria! Patella intorta SOW T ERBY, Genera of Shells, 

 Cephala, Patella, f. 5. Patella pectunculus GMELIX, Syst. xiii, p. 

 3713. Helcion pectinatus MOXTF., Conch. Syst. ii, p. 63. GRAY, 

 Guide Syst. Dist. Moll. B. M., p. 126 (descr. of branchiae). DALL, 

 Proc. Acad. N. S. Phila. 1876, p. 244 (dentition). 



This cap-shaped, scale-ridged black species is unlike any other 

 limpet, having much the contour of Scutellina. Linnaeus is gener- 

 ally but erroneously quoted as the authority for the name. It is a 

 common Cape species. 



Section PATIXA (Leach) Gray, 1852. 



Patina LEACH, Moll. Gt. Brit. (Gray's edition) p. 223, 1852. 

 GRAY, Syn. Br. Mus. 1840 (-name only no definition ; no type 

 mentioned). Ansates SOWB., Conch. Man. edit, ii, p. 68. Helcion, 

 Patella and Nacella sp., of authors. 



The branchial cordon is interrupted in front ; side of the foot with- 

 out an epipodial ridge or papilla. 



Dentition, pi. 52, fig. 2. Two inner lateral teeth on each side an- 

 terior, having simple cusps, the third lateral having a broad tri- 

 partite cusp. Formula of dentition ad 202 ^. 



Epipodial papillae have been ascribed to this group by a recent 

 authority, but I have satisfied myself that none are present by an 

 examination of specimens. The sides of the foot are as smooth as 

 in Helcioniscus exaratus. 



