340 DESCRIPTIONS OF CARIBBEAN MIOCENE FOSSILS. 



S. NUMisMALis, Gabb, n. s., PL 44, fig. 1, la. 



Shell depressed, broadly expanded laterally; spire small, not much elevated, 

 consisting of about four whorls ; suture minutely impressed ; surface marked only 

 by a few faint lines of growth ; umbilicus patulous ; details of mouth unknown. 



Figure. Natural size. 



Locality. With the preceding. 



From its shape, this seems to belong to the subgenus Cryptostoma, Blainv., but 

 the imperfect condition of the mouth of my only specimen renders the determina- 

 tion even of the genus, not to speak of the subgenus, somewhat doubtful. 



TBREBRA, Brug. 



T. DISLOCATA, Say. 



Cerithium id., Say, Journ. Phil. Acad., 1 Ser. v. 2, p. 236. 



Of this well-known recent species, found on the Atlantic coast of the United 



States, and fossil in the Santo Domingo miocene, I obtained a few specimens from 



Sapote, Costa Rica. I have compared them carefully with specimens of the recent 



shells in the museum of the Academy, possibly Say's original types, and I am 



satisfied in the identification. 



T. EvANSii, Gabb, PL 44, fig. 8. 



id., Gabb, Proc. Phila. Acad. 1860. 



Shell unusually short and thick for a member of this genus— resembling more 

 in its form an Obeliscus. Whorls scalariform, flat, and nearly vertical on the sides, 

 and truncated on top adjoining the suture. Surface, besides the lines of growth, 

 generally, though not in every case, carries one impressed revolving line a little 

 above the middle of the volution. Mouth moderate, ending in a short twisted, 

 notched canal, as is characteristic of this genus. Inner lip encrusted with a smooth 

 shining layer, columella ending in a twisted fold in front, and carrying another above. 



Figure. Natural size. 



Locality. I described this, with one or two other fossils, a number of years ago, 



out of a collection made by Dr. John Evans, United States geologist, who went 



officially to Chiriqui Lagoon, State of Panama, to examine some miocene coal 



beds. I pronounced their age then, on rather scanty material, but my own later 



observations on the same coal deposits in Costa Eica, amply confirm the old 



determination. 



STROMBUS, Linn. 



S. PUGILIS, Linn., Syst. Nat. (12 Ed.), p. 1209. 



For synonymy see memoirs on Sto. Domingo, Tr. Amer. Phil. Soc, v. 15. 



Although Mr. Guppy (.Quart. Journ. Geol. Soc, 1876, p. 521) gives his reasons 



