INSTITUTE OF SCIENCE, PHILADELPHIA. I3I 



Genus PHOS Montfort. 

 Phos parvus var. intricatus Dall. 

 Triton parvus C. B. Adams, Contr. Conch., p. 59, 1850. 

 Plios intricatus Dall, Proc. U. S. Nat. Mus. vi. p. 325, pi. 10, fig. 9, 1883. 

 Pliocene beds of the Caloosahatchie. 



Recent, in shallow water from Florida to Anguilla and along the eastern 

 coast of Mexico. 



The fossils are identical with the recent shells of the variety intincatus. 



Phos sp. indet. 



Miocene of Ballast Point, Tampa Bay in the silex-beds. 



Imperfect specimens of a species of Plios have been collected by Mr. 

 Burns at Ballast Point. 



It has, on the spire, three, on the last whorl nine or ten, primary spirals, 

 each pair with two or three much finer intercalary threads, crossing numerous 

 (9-15) narrow, transverse riblets, with wider interspaces, which extend as far 

 as the whorl ; the primary spirals are slightly swollen at the intersections ; 

 the lines of growth are rather strong ; the nucleus is smooth and two-whorled 

 and there are five subsequent whorls, which are but moderately rounded ; 

 the suture is very distinct ; the canal is short and twisted, with a marked fasciole ; 

 the outer lip thickened and sharply lirate inside ; the pillar anteriorly keeled. 

 Max. Ion. of shell 10.5 ; of aperture 4.5 ; max. diam. of shell 4.5 mm. 



The specimens of this species are all defective. It recalls in a general way 

 the appearance of Tfitonidea pauper, except that its transverse riblets are nar- 

 row and continued to the canal and that the shell is more acute, more slender 

 and with a relatively longer spire in proportion to the last whorl. 



To this genus belong Biiccitriton sagemnn Conrad (+ Nassa cancellata Lea) 

 and Nassa or Tritia mississippiensis of Conrad, both of the Upper Eocene. 



Genus ENGINA Gray. 

 Eng-ina turbinella Kiener. 

 Ricinula turbinellaK.\ener, Mon. Purpura, p. 29, pi. 9, fig. 25. 

 Engiiia turbinella Tryon, Man. v. p. 192, pi. 62, figs. 38, 39. 



Pliocene beds of the Caloosahatchie and Shell Creek. Recent in the West 

 Indies, from Key West, Florida, southward to Jamaica, etc. 



The fossils do not differ appreciably from the less compact variety of the 

 recent shell. The most common form of the latter has the sutures less de- 

 fined and the shoulder more sloping, but this is an unconstant character. 



