350 DESCRIPTIONS OF NEW SPECIES OF FOSSILS 



the fossils leads me to believe that Sowerby's name of M. Domingensis (Quart. 

 Journ. Geol. Soc. v. 6, p. 49, PI. 10, fig. 5) should be added as a synonym. The 

 shells, both recent and fossil, vary considerably in the length, and even in the pre- 

 sence or almost total absence of spines on the varices, and the length and direction 

 of the canal is by no means constant. All three forms are represented by the 

 series before me, as they are also in the Santo Domingo Miocene collection, and 

 specimens sent me by Mr. Guppy, from Trinidad, only serve to confirm my opinion. 



M. (Chiooreus) calcitkapa, Lam., A. S. V., v. 9, p. 513. 



Fossil from the Miocene ; found living in the West Indies, whence it was de- 

 scribed by Lamarck, under the name of hrevifrons. 



FUSUS, Lam. 

 F. Henekeni, Sby., Q. J. G. S., v. 6, p. 49, PI. 45, fig. 31. 



There is a single specimen in the collection, having all the details of character 

 of the common Sto. Domingo fossil, except that of size, being 5.5 inches long, and 

 1.5 inches wide. As is usually the case with larger shells, the longitudinal ribs 

 are not clearly defined on the last volution, and the specimen suggests irresistibly 

 a transition to the form of F. Dupetit-Thouarsii, of Kiener (Icon. coq. viv., p. 5, 

 PI. 11), from the Galapagos Islands, and with specimens of which I have compared 

 it. Mr. Guppy's identification of F. Haitensis as only a variety of F. Henekeni 

 was a fortunate discovery, coming as it did just before the finding by me of this 

 somewhat aberrant form on the main land. Had my shell been picked up on the 

 shores of the Galapagos Islands, or found in a tertiary deposit on the South Ameri- 

 can Pacific coast, no one would hesitate to call it F. Dupetit-Thouarsii. It was 

 found on the Atlantic side, and yet why is it not equally that species 1 But there 

 are also points of resemblance to the San Domingo shell ; and the inference is, 

 that the latter, extinct in Atlantic waters, still exists, and very little modified, ex- 

 cept in size, in the Pacific. 



MELONGENA, Schum. 

 M. MELONGENA, Linn., sp. 



For remarks on this species, sefe my Memoir on Santo Domingo, Tr. Amer. 



Phil. Soc, 1873, p. 205. ' • 



TURRIS, Bolt. 

 T. (Drillia) militaris, Hds., sp. 



For synonymy see Tr. Am. Phil. Soc, 1814, p. 23T. 

 Fossil in the West Indian Miocene, and living at Panama (Hinds). But a 

 single small specimen occurs in the collection. 



