FINN A. 



PiNNM 



Species 2. (Miis. Cuming.) 

 5EMINUDA. Finn, testa trigond, truncata, latere 



postico lonyitiidinaliter costalo, viultuqttamoso, squamis 

 tetmibus, erecth, latere antico squamis copiosis minutis, 

 versus umbones subobsoletis, rugis perpaucis amplls 

 coHcentricis ; sordid^ olivacea. 

 The half-naked Pinna. Shell triangular, truncated, 

 posterior side longitudinally ribbed, many-scaled, 

 scales delicate, erect, anterior side witli the scales plen- 

 tiful, minute, rather obsolete towards the umboes, 

 with a few large concentric wrinkles ; dull olive. 

 Lamaeck, Anim. sans vert. vol. vii. p. (51. 

 Pinna squamosvssima, Pliilippi. 

 Hab. South Carolina. 



This species, of a dull olive horny substance and pecu- 

 liarly truncated form, is densely sculptured on the poste- 

 rior angle with delicate, erect scales, while on the anterior 

 angle the scales are even more numerous, but smaller, 

 and, being almost obsolete towards the umboes, impart a 

 comparative smoothness to that portion of the shell. 



■Species 3. (.Miis. Cuming.) 



Pinna rotundata. Finn, testa elongato-trigond, extre- 

 mitafe rotundatd, radiatim subflexuoso-Uratd, undique 

 densissimi squamosa, squamis peculiariter irregulari- 

 hus, quasi papillaribns ; griseo-ntfescente. 

 The rounded Pinna. Shell elongately triangular, 

 rounded at the extremity, radiately subflexuously 

 ridged, everywhere very densely scaled, scales pecu- 

 liarly irregular, as though papillary ; greyish-red. 

 LiNNiBUS, Syst. Nat. p. 1160. 

 Pinna squamosa, Gmelin. 



Pinna marina, Chemnitz. 

 Hab. Mediterranean. 



This well-known species, an inhabitant chiefly of the 

 Mediterranean, is the lari^est of the genus, growing fre- 

 quently to two feet in length. The scales with which it is 

 everywhere densely beset have a peculiar papillary look, 

 and are distorted promiscuously in all directions. It is of 

 this species that the fine silken byssus has been sometimes 

 used for the manufacture of a pair of gloves. 



March, 1858. 



