308 AMERICAN JOURNAL 



33. P. annuliferum, Conr. Figs. 71 — 74. Elevated, sub- 

 couical; whorls 10 — 11, flattened, with elevated revolving 

 striaj ; suture obsolete; aperture sub-rhomboidal, very dis- 

 tinctly channelled at the bass. Dark brown, within white or 

 purplish. Ala. 



Fig. 73 is from the type of M. Ordiana, Lea. 



34. P. Brumbyi, Lea. Fig. 75. Pyramidal, rather thick ; 

 spire very much elevated, carinate at apex ; suture obsolete ; 

 whorls 10 — 12, but slightly convex, thickly covered with ele- 

 vated revolving strite ; aperture rather large, sub-rhomboidal, 

 with a much twisted channel at base. Deep reddish-brown, 

 reddish within. Coosa River, Ala. 



35. P. Currierianum, Lea. Fig. 76. Very narrow, much 

 elevated, sub-cylindrical; spire attenuate, with linear suture; 

 whorls 10 — 12, planulate, the body whorl angulate in the 

 middle, with one or two striae below; aperture small, sub- 

 rhomboidal, but little twisted below. Horn-color, banded 

 with dark brown. Florence, Ala. 



e. Plicate species. 



36. P. Sycamorense, Lea. Fig. 77. Conical, rather thick; 

 spire attenuate, pointed; suture impressed; whorls 11, some- 

 what convex, carinate above, plicate in the middle. Yellow- 

 ish horn-color, whitish within. Sycamore, Claiborne Co., E. 

 Tenn. 



37. P. plicatum, Tryon. Fig. 78. Ovate conical, attenu- 

 ate ; upper whorls closely plicate, lower ones smooth ; whorls 

 8, flattened, the last angulate on the periphery, and convex 

 below; aperture produced below. Light green, with a lighter 

 band below the suture, and two or three brown bands. Nash- 

 ville, Tenn. 



f. Smooth, angulate species. 



38. P. elevatum, Say. Figs. 79 — 81. Acutely turrited; 

 spire much elevated, sharp near the apex, carinated; suture 

 linear; whorls 10, flat, angulate on the periphery, smooth or 

 obsoletely striate; aperture rhomboidal, with a well developed 

 channel. Olivaceous or dark horn-color, with or without 

 bands, whitish or reddish within, W. Tenn. {?), Ohio River, 

 and the rivers of the North- Western States. 



Tlie first figure is a smooth adult shell, aad represents P. elongatttm, Lea. 



