384 A MANUAL OF AMERICAN LAND SHELLS. 



is less globose than the former aud more sparingly hirsute. It differs 

 widely from both in the character of the umbilicus ; the aperture is 

 much like that of pitstida, but more narrow than that of leporina. The 

 inferior tooth on the peristome is more developed laterally than in pus- 

 tula; indeed, it has a somewhat bifid appearance, in which respect it 

 is more allied to leporina. 



The fulcrum in pustuloides is of the same nature as that in leporina, 

 but less developed aud with the outer edge entire. 



As to the station of the species, I copy the following from one of Dr. 

 Wilson's interesting letters from Darien, Ga. : — 



"The i)lace has an eastern exposure to the sea, high tides rising to 

 the base of the low bluff where they exist. The growth of trees, which 

 consists mostly of live oak and Celtis occidentalism has never been 

 cleared off; the Palmetto serrnlata flourishes as an undergrowth. The 

 soil is covered for a few inches in depth with oyster-shells thrown there 

 by the Indians, and decayed leaves and fragments of branches are of 

 course over all these, under which, and among the superficial oyster- 

 shells, the Helices live. P. pustula is nowhere near, or at least a rigid 

 search did not reveal anJ^ Macrocyclis concava (dead) occurs in small 

 numbers, Triodopsis inflecta abundantly." 



Jaw as usual in the genus; over 10 ribs. 



Lingual membrane with 17-1-17 teeth, 8 laterals, the ninth tooth 

 having bifid inner cutting point (Terr Moll., V, Plate VI, Fig. C). 



Genitalia unobserved. 



TRIODOPSIS. (Seep. 283.) 



Triodopsis Hopctoiicnsis, Shuttleworth. 



Shell with a narrow, scarcely pervious umbilicus, depressed-globose, 

 Fig. 418. with numerous rib like striae, olive horn-color; sj^ire ob- 

 tuse, convex; Mhorls 5^, rather convex, the last scarcely 

 deflected in front, constricted at the aperture ; aperture 

 lunar, tridentate ; a moderate, tongue-shaped, slightly 

 entering parietal denticle ; peristome reflected, within 

 T. Hopetonensis. thickcued with a white, light callus, its right margin with 

 a small, somewhat anterior denticle, its basal terminus with a marginal 

 denticle. Greater diameter 13, lesser 11"""; height, 6""". 



Helix Hopetonensis, Shuttleworth, Bern. Mitt., 1852, 198. — Reeve, Con. Icon., No. 709 

 (1852).— Pfeiffer, Hon. Hel. Viv., iii, 263 ; in Chemnitz, ed. 2, 420, pi. cxiviii, 

 figs. 17, 18 (pi. Ixiv, figs. 7-9?). —Gould, Terr. Moll., iii, 17. —W. G. Binney, 

 Terr. Moll., iv, 72, pi. Ixxvii, fig. 16 ; L. & Fr.-W. Sh., i, 132, fig. 224 (1869). 



