92 Binney on Terrestrial Motlusks. 



HELIX VOLVOXIS Pakreyss. 



Plate LXXVIIl. Figure 17. 



T. umbilicata, orbiculato-oonvexa, tenuis, rufo-cornea, pellucida, regular- 

 iter costulato-striata ; spira brevissinia, convexa ; anf. 7 convex!, regulariter 

 accrescentes, ultimus rcliquis superne vix latior, angulatus, infra angu- 

 lum inflatus, striatus, nitidus ; umbilicus latus, regularis, anfractu ultimo 

 latissimo reliquis regulariter decrcscentibus ; apertura majuscula, reni- 

 formis ; perist. intus callosum, reflexum, marginibus callo brevi, triangu- 

 lari dentilbrmi junctis. Diam. maj. 9, min. 8, alt. 4 mill. (Pfeiffer.) 



SYNONYMS AND REFERENCES. 



Helix volvoxis Parreyss in Pfeiffer Symb. iii. p. 80; Mon. Hel. Viv. i. p. 409; 

 iii. p. 262. 



Chemnitz, ed. 2,1. 379 (1846), pi. Ixvi. figs. 4-6, (1849). 



Reeve, Con. Icon. No. 12-37, (1854). 

 Polygyra septemvolva Beck ? abs. desc. teste Pfr. 



This species is readily distinguished by its smoother 

 surface, its uniform color, and its regular under surface, 

 exhibiting fewer volutions than any of the other forms. 

 I have not detected any internal lamina. It is also the 

 smallest of the group. I have it from St. Simon's Isle, 

 Georgia, (Postell,) and Jacksonville, Fla. (Dorman.) It 

 occurs in immense numbers. The outside figures on pi. 

 38, and the upper line of pi. 39, are probably drawn from 

 varieties of this species. 



HELIX HINDSI Pfeiffbe vol. iii. p. 17, pi. Ixxviii. figs. 5, 6, 8. 



Helix Mndsi Pfeiffer, 1. c. iii, 265. 



Reeve, Con. Icon. No. 712, (1852). 



I have added to an enlarged view of the aperture on pi. 

 78, outlines of Pfeiffer's figures in Chemnitz. 



HELIX LEPORINA Gould vol. ii. p. 199,pl. xl. a. fig. l.* 



Helix leporina Reeve, Con. Icon. No. 722, (1852). 



Bland, N. Y. Lye. vi. 348; Notes, 39. 

 Helix puslula (3 Pfeiffer, Mon. iii. 268. 



This species reaches a much more northern limit than 



