108 



LAND AND FRESH- WATER SHELLS jOF N. A. [PART T. 



Eelix carpenteri- 

 ana, eularged. 



Fig. 183. very oblique, lunate ; peristome callous within, thickened, 



little reflected, the margins joined by a triangular denti- 

 form lamella. Greater diam. 10, lesser 9 ; height 4 mill. 



Helix microdonta, Pfeiffer, Mon. Hel. Viv. 409, ex 

 parte? (184S).— W. G. Binney. Terr. Moll. IV, 91, 

 pi. Ixxviii, f. 28, excl. fig. 



Helix carpenter i ana, Bland, Ann. N. Y. Lye. VII, 137. 



Polygyra carpenteriana, Tkyon, Am. Journ. Conch. Ill, 

 159, pi. xi, f. 24, not 23 (1867). 



Florida, from St. Augustine through the Keys. 

 This species has been hitherto named H. micro- 

 donta in American cabinets. It is readily dis- 

 tinguished from all the other species of the group 

 by its strong acute rib-like stri^, and the peculi- 

 arity of the outer whirl. About the last third of it, behind the 

 aperture, is ribbed and tumid ; the whirl is then rather abruptly 

 contracted, becoming narrower above, and flattened and slightly 

 striated beneath, but again, as it passes towards and beneath the 

 aperture, dilated and convex. This change of form gives to 

 the last whirl a distorted appearance. The internal lamina is on 

 the coluraellar wall of the contracted and flattened portion of the 

 last whirl, and runs obliquely, in the direction of the aperture, 

 attaining a length in a large specimen of about 6 mill. The 

 character of the aperture is most like that of ^. cereolus, but in 

 that species the last whirl has none of the peculiarities above 

 described. The internal lamina is found in a majority of speci- 

 mens, but not in all ; it can generally be seen through the outer 

 wall of the shell. 

 The upper figure is engraved directly from a photograph on wood. 



Fig. 184. Helix felligeri, Bland. — Shell umbilicate, orbicu- 



lar, flat, thin, shining, pale or reddish horn-colored, with 

 rather distant rib-like striie above, finely striated beneath ; 

 spire almost level ; suture deep ; whirls five and a half to 

 six, rather convex, regularly increasing, the last angular 

 at the periphery, inflated below; umbilicus funnel-shaped ; 

 aperture oblique, kidney-shaped ; peristome thickened, 

 little reflected, the margins joined by a strong triangular 

 Btlix febigeri. callus. Greater diam. 8^, lesser 72 ; height Si mill. 



