I Z HBLICEA. 



The shell mentioned on page 10 of my Notes as being 

 furnished with an internal fulcrum, seems to be a distinct 

 species. 



I have specimens of fall ax from the Northern, Western, 

 and Southwestern States. It is also found in many of the 

 Southern States, and is quoted from Texas by Roemer. 

 Say's description is as follows : — 



Helix fallax. Spire convex; volutions five, with elevated 

 lines forming grooves between them ; labi'um reflected, contracting 

 tlie aperture, bidentate ; teeth separated by a profound sinus ; 

 superior tooth inflected into the mouth ; inferior tooth situated 

 near the base ; labrura with a large, prominent, oblique, lamelliform 

 tooth, curving downwards so as nearly to reach the termination of 

 the labrum ; umbilicus open, exhibiting the volutions. 



Greatest transverse diameter nine-twentieths of an inch. 



This resembles the tridentata Nob., but the upper tooth of the 

 labrum is much inflected, the spire is more elevated, and the size is 

 less considerable ; in the former character it coincides with H. 

 injlecta Nob., but that shell has the umbilicus closed. 



Presented to the Academy by Messrs. Hyde and Mason, who 

 found it in the vicinity of Philadelphia, where it is not uncommon. 



Since the above was written, 1 received a specimen from Mr. 

 Stephen Elliott, of South Carolina, fully equal in size to the 

 tridentata. 



HELIX HOPETONENSIS Shuttleworth. .vol. iii. p. 17, pi. Ixxvii. fig. 16- 



Helix Hopetonensis Shuttleworth, Bern. Mitt. 1852, p. 198. 

 Reeve, Con. Icon. No. 709, (1852). 

 Pfeiffer, Mon. Hel. Viv. iii. 263. 

 Chemnitz, ed. ii. p. 420, pi. cxlviii. figs. 17, 18. 



I have it also from Florida, and St. Simon's Isle, Geor- 

 gia. (Postell.) 



HELIX VENTROSULA Pfeiffek. 

 Plate LXXVII. Figure 14. 



T. rimato-perforata, depresso-globosa, tenuis, subtiliter striata, pellu- 

 cida, corneo-albida ; spira vix elevata; anfr. 5 vix convexiusculi, ultimas 



