OP CONCHOLOGY. 30T 



26. P. tortum, Lea. Fig. 59. Conical, smooth, rather 

 thick ; spire obtusely conical ; suture much impressed ; whorls 

 7, flattened, the last large and rounded below; aperture large, 

 sub-rhomboidal, obtuse, broadly rounded below; lip scarcely 

 sinuous ; periphery sometimes with three or four obscure 

 stride. Horn-color, white or brownish within. Little Uchee 

 River ^ Geo. 



27. P. dignum, Lea. Fig. 60. Sub-fusiform, thick, slight- 

 ly noduled ; spire raised, conical ; suture well impressed ; 

 whorls 8, flattened, the last large and convex, with several 

 raised lines ; sometimes the periphery is obscurely tubercu- 

 late; aperture ovately rhombic, produced obtusely at base. 

 Honey yellow, with a single narrow band below the periphery, 

 salmon or white within. Yellow Leaf Greek. Ala. 



d. Carinate., striate Phurocerse. 



28. P. unciale, Hald. Figs. 61 — -QQ. Acuminately tur- 

 rited; spire subulate, strongly carinate ; suture linear; whorls 

 12, the last convex, with two or three obscure angles ; aper- 

 ture oval, channel short and broad, Horn-color. East and 

 Middle Tenii.., North Ala. 



Fig. 61 is typical, Fig. G2 is sugillatum, Reeve, Fig. 63 bicostatum, Antli., 

 Fig. 64 oblitum, Lea, and Figs. 65 and 66 rigidum^ Anth. 



29. P. subulare, Lea. Fig. 67. Acutely turrited, rather 

 thin; spire much elevated; apex acute; whorls 12, flat, cari- 

 nate at apex ; body whorl angulate on the periphery. Horn- 

 color, generally light yellow and bluish ash below the suture. 

 Great Lakes, Niagara and St. Lawrence Rivei^s, Erie Canal. 



30. P. subulaeforme, Lea. Fig. 68. Acutely turrited, rather 

 thin; spire attenuate ; suture much impressed; whorls 10, all 

 slightly carinate, body with two or three raised lines; aperture 

 small, channel very wide, obtuse. Horn-color. Knoxville, 

 Tenn. 



A stouter shell than No. 39, with the caringe less marked, and revolving 

 on the middle of the whorls of the spire, instead of their base. It is dif- 

 ferent in color, being light horn, without variation. 



31. P. Henryanum, Lea. Fig. 69. Attenuate, subulate, 

 carinate, thin, semi-transparent; spire elevated; suture im- 

 pressed ; whorls 10, flattened, the last angulate on the periph- 

 ery, and 6-striate below; aperture small, sub-rhomboidal, lip 

 very sharp and sinuous. Pale horn-color, not banded. Tenn. 



32. P. Lewisii, Lea. Fig. 70. Sulcate, somewhat thin, 

 conical, elevated ; spire much elevated, with indistinct suture ; 

 whorls 11, flattened, covered with sulcations, of which there 

 are 4 to 5 on the body, which is angulate on the periphery. 

 Horn-color or dark iDrown, banded or without bands, white 

 or purple within. Lllinois. 



Narrower and thinner than the next species ; it i* also from a far re- 

 moved locality. 



