ART. 22 MIOCENE GASTROPODS AND SCAPHOPODS MANSFIELD 33 



the whorls, being more prominent on the last whorl. Aperture about 

 one-half the length of the shell, semiovate in outline; its anterior 

 extremity forms a wide, short, rounded, reflected canal emarginating 

 the anterior extremity. A small chink is behind the smooth calloused 

 columella. 



Dimensions: Type (U. S. Nat. Mus. Cat. No. 352664) measures: 

 Altitude 10.5 mm. ; greatest diameter 6.5 mm. ; length of aperture 

 6.5 mm. 



The genus is found in the Recent fauna along the western coast of 

 Africa. 



Occurrence. — Upper Miocene: Caroni County, Springvale, near 

 Couva. 



Genus ANCILLA Lamarck 



ANCILLA LAMELLATA (Guppy) 



Andllctria lamellata Guppy, Geol. Soc. London, Quart. Journ., vol. 22, 1866, p. 

 579, pi. 26, fig. 9. 



Type locality: "Lower Miocene, Manzanilla, Trinidad, Guppy, 

 1866." There are in the United States National Museum (Cat. No. 

 115568) four specimens designated as types. 



This species- is separated from Ancilla 'paralamellata^ new species 

 collected from the Brasso beds by its more evenly conic spire and by 

 the undulating spirals on the early whorls. I find no close relative 

 to this species in outside deposits. Two specimens of this species 

 were collected from Manzanilla coast, station 9197, by J. A. Bull- 

 brook. 



ANCILLA PARALAMELLATA, new species 



Plate 5, figs. 2, 7 



f Ancilla lamellata Maury (? in part), Bull. Amer. Paleout., vol. 10, no. 42, 

 p. 197, 1925. 



Shell rather small for the group, semiovate, highly polished, spire 

 acuminate, slightly depressed behind the anterior suture, larger co- 

 type probably with about six whorls. Entire shell covered Avith a 

 thin wasli of callus except for a narrow area encircling the lower 

 half of the body whorl, beginning opposite the pillar and extending 

 to the margin of the outer lip ; a heavier callus on the body whorl 

 marginates the uncalloused area and extends parallel with the axis 

 of the whorl from the suture to the upper margin of the aperture. 

 Nucleus apparently consists of about one whorl. Spirally sculp- 

 tured mainly on the spire wliorls— early v.horls of about tAvo or 

 three striae separated by slightly raised areas; on the later Avhorls 

 the striae increase in number and the interstices flatten out. Behind 

 9116—25 P. 



