26 FOSSILS FROM SOUTHERN UNITED STATES— BALL. vol.xviii. 



spire; suture narrow, deeply channeled; spire just visible above the 

 sutural margin, toward which the posterior jiart of the last whorl is 

 evenly rounded over; aperture narrow behind, with a deep sutural 

 notch, the outer lip gently arched in the middle, thin and sharp, then 

 receding and gently rounded into the broad, conspicuous pillar, which 

 is obliquely arched and chiefly constituted by a single broad i^lait; the 

 body whorl is covered at the aperture by a thin layer of callus; there 

 is no notch or chink behind the pillar ; the anterior end of the shell is 

 rounded and attenuated in the same degree as the other end. Longi- 

 tude of shell, 6; maximum diameter, 3 mm. 



Habitai.—Dui^lin County, North Carolina (2279, 2280), at the Natural 

 Well and elsewhere. 



Types.— Noa. 113874, 113875, U. S. N. M. 



This pretty species is recognizable by the evenly rounded ends and 

 gently inflated form, which are not duplicated in any other of our 

 Miocene species. 



TORNATINA PERSIMILIS, new species. 



Shell small, short, subeylindrical, of about three whorls beside the 

 nucleus, the spire moderately prominent, somewhat variable as usual 

 in this group, the suture distinct, bordered by a narrow, shallow chan- 

 nel; aperture narrow behind, wider in front; outer lip thin, prominently 

 arched, and very slightly constricted in the middle; in front, rounding 

 gently into the pillar, which has a groove behind it, and is chiefly com- 

 posed of a single not much arched nor very prominent plait. Longitude 

 of largest specimen, 3; maximum diameter, 1.25 mm. 



Eabitat. — Chipola beds (2213), Calhoun County, Florida; a young 

 specimen from Oak Grove, Santa Eosa County, Florida, also probably 

 belongs to this species. 



Types.— yo. 112G07, U. S. N. M., and in the collection of Mr. Aldrich 



This species is the precursor and probably the ancestor of T. canali- 

 culata, Say, which appears in the Chesapeake Miocene and persists to 

 the present day. It diifers from it in its smaller size and by its (on the 

 average) more cylindrical shape, most of the specimens of canalicuhifa 

 showing a tendency to be widest at the shoulder of the whorl. The 

 Chipola specimens are more uniform than the ordinary canaliculata, 

 yet if they occurred in the same faunal horizon might fairly be regarded 

 as a dwarf race of that species. 



TORNATINA FISCHERI, new species. 



Shell small, ovate, rounded at both ends, spire almost concealed, of 

 two and a half whorls; body slightly wider behind the middle of the 

 shell; aperture as long as the shell, deeply notched at the suture, which 

 is channeled, but whose outer margins arch over and nearly conceal the 

 spire, probably closing altogether in some specimens; aperture narrow, 

 rather contracted in front, the outer lip thin, arched in the direction of 



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