102 
HELIX §. 20. 
mellari dilatato, patente. — Diam. maj. 30, inin. 26, ait. 16 mill. 
(Mus. Cuming.) 
Helix Kochi Pfr. in Proc. Zool. Soc. 1845. p. 127. 
Habitat . . . ? ^ 
^ 255. H. solitaria Say. 
T. late pervio -umbilicata, globoso-depressa , soiidiuscula, 
diaphana, oblique conferlim rugosa, lutescenti-cornea , brunneo 
2 — 3 fasciata; anfr. 6 convexi; sutura profunda; apertura lunato- 
rotundata, intus nitide alba, fasciata; perist. simplex, acutum, 
margine columellari dilatato, subreflexo. — Diam. maj. 25, min. 
22, ait. 15 mill. (Coli. Nr. 135.) 
Helix solitaria Say in Philad. journ. U. p. 157. 
— — Binn. in Bost. journ. HI. p. 426. t. 23. 
— — Pfr. Symb. n. p. 39. 
— — Chemn. ed. 0. Helix N. 145. f. 24. f. 5. 6. 
Eiiryomphala solitaria Beck ind. p. 8. 
Habitat in America boreali : Missouri , Ohio. 
256. H. alternata Say. 
• T. late umbilicata, orbiculato-depressa , tenuis, luteo-comea, 
strigis interruptis, rufis ornata, striis confertis elevatis scabra; 
anfr. 5/2 planiusculi, ultimus interdum obtuse carinatus; umbili- 
cus magnus, pervius; apertura perobliqua, lunato-ovalis; perist. 
simplex, acutum, ad umbilicum vix expansum. — Diam. maj. 21, 
min. 19, ait. 10 mill. (Coli. Nr. 136.) 
Helix alternata Say in Philad. journ. U. p. 161. 
— — Say in Nichols. Am. Enc. t. 1. f. 2. 
— — (Helicella) Fer. pr. 199. Hist. t. 79. f. 8. 9. 
— — Binn. in Bost. journ. III. p, 428. t. 25. 
— — Gould report p. 177. f. 114. 
, — — Chemn, cd. II. HelLx N. 146. t. 24. f. 17. 18. 
— scabra Lam. 83. p. 88. ed. Dh. p. 66. 
— radiata GmeL 73. p. 3674? 
Patula alternata Ileld in Isis 1 837. p. 916. 
Eiiryomphala altemoda Beck ind. p. 8. 
Lister t. 70. f. 69? (An potius H. solitaria?) 
/j? Carinata, junior ? Fer, t. 79. f. 10. 
Habitat iii America boreali in ripis fluviorum Mississippi, Missouri 
- A. ct Ohio uMassachusetts (Gould). ^ /« 
7 ^. dfp. -L atarrauct. 
257. H. discoides Lesson. 
T. discoidea, late umbilicata, fusco -rubra, fasciis albis 
minutissimis et regularibus ornata; anfr. angustissimi, ultimus 
