MUSEUM OF COMPARATIVE ZOOLOGY. 79 



A description of the soft parts of these species, with figures of the animal 

 taken from life, is in preparation. It is to be regretted that the account will 

 be rendered rather imperfect on account of the poor state in which the soft 

 parts have come to hand. The more delicate portions were entirely destroyed. 

 Those parts of importance in classification, being of a tougher nature, for the 

 most part can be tolerably well made out. Sufficient is already known to show 

 that the group possesses characters of family value, and stands nearest the 

 Trochidw, with features recalling Haliotidce; and that it has nothing whatever 

 in common with the Pleurotomidce. 



The other living species is Pleurotomaria Beyrichii Hilgendorf (Sitz. Ges. 

 Naturf. Fr., Berlin, Mar. 20, 1877), which is supposed to come from Japan seas, 

 though its habitat is not yet certainly known. Eight specimens altogether of the 

 three species are all at present recorded, only one being known of P. Beyrichii, 

 four of P. Adansoniana, and three of P. Quoyana. 



GENUS HALIOTIS Linne. 

 Haliotis (Padollus) Pourtalesii n. s. 



Shell about an inch and a half in diameter, above smoothish except for two 

 strong spiral ribs, the outermost of which was perforated with four or five 

 branchial holes ; general form subcircular ; color above, rich reddish orange, 

 within brilliantly pearly; whorls about two and a half ; spire flattened, not 

 prominent. 



Bed of the Gulf Stream in 200 fathoms, near the Florida Eeefs, Pourtales, 

 March 31, 1869. 



This species was obtained by the lamented Pourtales, and carefully examined 

 by me in 1870. It was represented by the only specimen ever obtained from the 

 region, and which was afterward destroyed in the Chicago fire. Its characters are 

 such as to be immediately recognizable if it were again obtained, and it seems 

 proper to associate the name of the discoverer with it, not only as being one of 

 his most notable finds among mollusks, but also as representing a remarkable 

 fact in geographical distribution which might otherwise be lost sight of. 



GENUS CREPIDULA Lamarck. 



< Patella Linne, Syst. Nat., ed. X. p. 781, 1758 ; ed. XII. p. 1257, 1767. 



< Crypta Humphrey, Mus. Cal., p. 4, Gen. V., May 1, 1797. No description. 



= Crepidida Lam., Prodr., p. 78, 1799 ; type Patella fornicata Liu. (not of Lam., 

 Syst., p. 70, \?>ni, = Navicella Lam.). Roissy, Moll., V. p. 234, 1805. 

 Fischer, Tabl. Synopt. Zoogn., p. 26, 1808. Auctorum. 



= Crepidulus Montfort, Couch. Syst., II. p. 87, 1810. 



= Proscenula Perry, Conch., pi. 53, 1811 ; type indeterminable. 



= Sandalium fi Schumacher, Essai d'un Nouv. Syst., p. 184, 1817. 



= Proxenula Ferussac, Journ. de Phys., t. 90, p. 285, 1820, as of Perry. 



