46 



Family FUSID^E. 



Shell more or less spindle-shaped, without varices ; the lip of 

 the aperture not thickened, 



Operculum ovate, acute, with apical nucleus. 



The animal possesses the essential features of a Murex. 



Dentition. That of the tj-pical genus Fusus does not differ es- 

 sentially from that of Fasciolaria; Stimpson states* that it has the 

 saw-like lateral teeth of Fasciolaria, whilst M acdonaldf found an- 

 other species to possess lateral teeth of the Muricoid type. Tros- 

 chel finds a Fasciolarioid dentition in Fusus Syracusanuv, and he 

 has accordingly made for it a new genus, Aptyxis ; but Schacko has 

 recently found the same dentition in Fusus inconstans Lischke, a 

 typical Fusus. I think that Macdonald must have mistaken some 

 other genus for Fusus. The dentition of Sipho, which, according 

 to Troschel, resembles that of Fasciolaria is shown by the more 

 recent investigations of Sars to be Buccinoid , Ptychatractus, with 

 evident resemblance to Fasciolaria has a peculiar dentition, ap- 

 proaching Murex, and on this character alone Stimpson, followed 

 by Gill, assigns to it a distinct family. 



Neptunea, Melongena, etc., long classed with Fusidae are now 

 brought into more intimate relationship with Buccinum, and 

 Busycon, and Tudicla will go into the same group ; on the other 

 hand Peristernia, Latirus, etc., formerly included in Turbinellidee 

 have a Fasciolarioid dentition, which, with added conchological 

 characters may suffice for their removal from that to the present 

 family. Stimpson j describes and figures the dentition of an 

 unknown species of Peristernia from the coast of Georgia, which 

 lias the essential features of Busycon* and he thereupon places 

 the genus in Neptuniin^e ; but it is evident that he was in error, 

 as Troschel figures known species, which are Fasciolariform in 

 dentition as they are in conchological characters. 

 Sub-family Fusinse. Columella not plicate, not tortuous. 

 Sub-family Fasciolariinse. Columella tortuous with oblique plaits 



or plications. 



* Am. Jour. Conch. I, 54. 



f Ann. Mag. Nat. Hist., 4th Ser. II, 243. 



Am. Jour. Conch., I, 60. 



