108 TERRESTRIAL AIR-BREATHING MOLLUSKS. 



Helix subplana, BINNEY, Bost. Journ. Nat. Hist., IV. Part I. cover, p. 3 (1842) ; 



IV. 241 (1842); Terr. Moll., II. 229, PI. XXXIII. PFEIFFER, Hon. Hel. 



Viv., I. 112. W. G. BINNEY, Terr. Moll., IV. 110. ' 

 Hijalina subplana, TRYON, Am. Journ. Conch., II. 250 (1866). 

 Zonites subplanus, W. G. BINNEY, L. & Fr.-W. Sh., I. 288 (1869). 



A species of the Cumberland Subregion, having been found in Eastern 

 Tennessee and Lawrence County, Kentucky. It has also been found in West- 

 ern Pennsylvania in the mountains. 



The only American species which this shell can be said to resemble is Z. 

 inornatus, which in size and color is quite like it, and at first sight may be taken 

 for it. It differs from it in the following particulars : The upper and lower 

 surfaces are both more flattened, and the outline is a more perfect circle. The 

 number of whorls, in specimens of the same size, is greater by nearly one volu- 

 tion. The surface of the whorls is less rounded ; the last whorl expands but 

 very little towards the aperture ; the base is broader, less indented, and very 

 flat ; the umbilicus is rounder, and better denned ; and the aperture is not 

 thickened within by a white, testaceous deposit. 



It is an extremely rare species. 



Animal unknown. 



Zonites inornatus, SAY. 

 Vol. HI. PL XXXIV. 



Shell depressed ; epidermis yellowish horn-color, smooth, shining, with very 

 minute lines not breaking the smoothness of the surface ; whorls 5 ; suture 

 not much impressed ; aperture transverse, scarcely oblique, obliquely lunar, 

 with a thick, white testaceous deposit around its whole inner surface, a little 

 distant from the margin ; peristonie thin, acute, fragile, its ends somewhat con- 

 verging, the columellar margin reaching to the centre of the base, subdilated 

 above ; umbilicus small ; base rather flattened, indented in the centre. Greater 

 diameter 16, lesser 12^ mill.; height, 6 mill. 



Helix inornata, SAY, Journ. Acad. Nat. Sci. Philad., II. 371 (1821) ; BINNEY'S 

 ed. 24. BINNEY, Bost. Journ. Nat. Hist., III. 419, PI. XXI. Fig. 3 (1840) ; 

 Terr. Moll., II. 227, PI. XXXIV. DEKAY, N. Y. Moll., 39 (1843). ADAMS, 

 Vermont Mollusca, 161 (1842). PFEIFFER, Mon. Hel. Viv., I. 84; IV. 48. 

 W. G. BINNEY, Terr. Moll., IV. 109. MORSE, Amer. Nat., I. 314, Figs. 19, 

 21, 22 (1867). 



Helix glapliyra, PFEIFFER, olim, Symbols, II. 29, excl. syn. fuliginosa ; Mon. 

 Hel. Viv., I. 57. REEVE, Con. Icon., 667. Not SAY. 



Helix inornata, BINNEY, not SAY, BLAND, Ann. N. Y. Lye., VII. 127. 



Hyalina inornata, TRYON,Am. Journ. Conch., II. 249 (1866). 



Zonites inornata, W. G. BINNEY, L. & Fr.-W. Sh., I. 289 (1869). GOULD and 

 BINNEY, Inv. of Mass., ed. 2, 453 (1870). 



Animal with head, neck, and eye-peduncles bluish-black ; foot whitish. 

 Eye-peduncles long and slender. A marginal furrow extending along the 



