HELIX §. 55. 291 



^S. Minor, cingulis distantibus 6 — 7 lateritiis: diam. maj. 18, min. 16, 

 alt. \\ mill. (Spec.) 



Helix multilineata var. Chemn. 1. c. t. 71. f. 19. 20. 

 Habitat in America boreali: Ulinois ot Missouri. 



759. H. pennsylvanica Green. 



T, obtecte perforata, subglobosa, tenuis, pellucida , luteo- 

 cornea, subtiliter oblique coslulata; anfr. 5 planiusculi, ultimus 

 ad aperturam subconstrictus; apertura lunaris; perist. late re- 

 flexum, intus albo-Iabiatum, margine columellari subrecto, ex- 

 panso, umbilicum obtegente. — Diam. maj. 17, min. 15, alt. 11 — 

 12 mill. (Coll. Nr. 463.) 



Helix pennsylvanica Green Contrib. to Maclurian Lyc. N. 1. p. 8. 



— — Binn. in Bost. journ. L p. 483. t. 16. 



— — Pfr. Svmb. IL p. 36. 



— — Chemn. ed. IL Helix N. 442. t. 73. f. 4. 5. 



— clausa Say in Philad. journ. II. p. 154. Nec Rafin. 



— — Suy Amer. Conch. t. 37. f. 1. 



— — Binn. in Bost. journ-. I. p. 482. t. 15. 

 Tridopsis thyroidus var. edentula Beck ind. p. 2 3? 



Habitat in America boreali: Pennsylvania , Ohio, lllinois. 



Obs. Diffeit cib H. muUilineata spira elatiore et lamina umbihcum oble- 

 genle multo minus expansa , ab H. thyroitle umbilico omnino clauso , apertura 

 edenlula, etc. 



760. H. Mitchelliana Lea. 



T. superne obtuse conica , inferne inflata , longitudinaliter et 

 subtiliter striata, cornea, diaphana, imperforata; anfr. 5; aper- 

 lura subrotundata; labrum subreflexum ; columella laevis. — 

 Diam. 0,7, long. 0,4 poll. (Lea.) — Diam. maj. 19, alt. 12 mill. 

 (exic.) — CoII. Nr. 464? 



Helix Mitchelliana Leaohs. 11. p. 87. t. 23. f. 7L 



— — ? Chem7i. ed. 11. Hehx N. 332. t. 56. L 6 — 8. 



Habitat in America boreali : Ohio. 



b s. <" Afflnis clausae et jejunae Say. Slriac majores, quam harum; labrum 

 magis aculum, quam clausae». — Conf. H. ihyroides Nr. 900. 



761. H. plicaria Lamarck. 



T. obtecte perforata, orbiciilato-depressa, violacescenti-fusca, 

 basi pallidior, oblique granulato-coslata; anfr. 4^2 convexi, ulti- 

 raus antice valde deflexus; apertura subhorizontalis, angusta, 

 subovalis, inlus alba; perist. acutum, angulatim latissime expan- 

 sum, intus incrassatum, marginibus callo junctis. — Diam. maj. 

 20, min. 16, aU. 10 — 11 mill."(Coll. Nr. 465.) 

 Helix plicaria Lam. Euc. meth. t. 462. L 3. 



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