HYALINA. 



49 



Fig. 78. 



Hyalina lasmodon, Phillips. — Shell very mucli flattened above, 

 a little convex ; epidermis corneous, shining ; whirls seven, narrow, very 

 slowly increasing in diameter from the apex to the aperture, and not ex- 

 panding at the aperture, with minute, transverse striae and 

 wrinkles ; suture moderately impressed ; peristome thin, 

 acute ; aperture nearly circular, within, upon the base, are 

 two prominent, white, testaceous laminae, nearly parallel, 

 and extending far into the cavity of the whirl ; umbilicus 

 large, rather expanded, and deep ; base smooth, well rounded 

 from the umbilicus to the circumference. Greatest diam. 6, 

 height 2^ mill. 



Helix lasmodon, Phillips, Journ. Acad. Nat. Sci. VIII, 182 



(1842) ; Proc. of same, I, 28 (1841).— Bixney, Terr. Moll. II, 254, 

 pi. xxxvii, f. 2.— DeKay, N. Y. Moll. 47 (1843).— Pfeiffer, Mon. 

 Hel. Viv. Ill, 142.— W. G. Binney, Terr. Moll. IV, 122. 

 Helix macilenia, Shdttleworth, Bern. Mit. 1852, 195. — Gould, Terr. 



Moll. Ill, 20.— Pfeiffer, /. c. Ill, 640. 

 Gastrodonta lasmodon, Tryon, Am. Journ. Conch. II, 257,pl.iv,f. 40(1866). 



In the mountains of northern Alabama and eastern Tennessee. 



Hyalina interna, Say. — Shell very narrowly perforated, de- 

 kjressed, slightly convex ; epidermis reddish-brown, shining ; whirls eight, 

 with regular, equidistant, elevated, oblique, rounded ribs, 

 separated by distinct grooves ; suture deeply impressed ; aper- 

 ture flattened, transverse, narrow ; peristome thin, acute, 

 thickened internally ; within the base of the aperture, some- 

 what distant from the margin, are two prominent, sub-lamelli- 

 form, white teeth, not reaching the edge of the peristome ; 

 base smooth, polished, umbilical region indented. Greater 

 diam. 5J, height 3^ mill. 



Helix interna, Sat, Journ. Acad. II, 155 (1822) ; Binney's 

 ed. 18.— Binney, Bost. Journ. Nat. Hist. Ill, 405, pi. 

 xxi, f. 1 (1840) ; Terr. Moll. II, 247, pi. xxx, f. 4.— 

 DeKay, N. Y. Moll. 46 (1843).— Chemnitz, 2d ed. I, 200, tab. ci, f. 

 1-4. — Pfeiffer, Mou. Hel. Viv. I, 183. — Reeve, Con. Icon. 718. — 

 W. G. Binney, Ter. Moll. IV, 121. 



Helix pomum-adami. Green, Doughty's Cab. Ill, 35 (1834). 



Gastrodonta interna, Tryon, Am. Journ. Conch. II, 258, pi. iv, f. 42 (1866). 



From the Alleghany Mountains to Missouri ; Ohio to (xeorgia. 



The teeth within the aperture are in general formed of a single 

 prominent lamina, or tooth-like fold ; but sometimes one, or both 

 of them, are bifid, or even trifid. A second set often, and some- 

 times a third set of teeth are seen through the transparent base 

 of the shell, irregularly striated, but generally having equal 

 4 July, 1868. 



