104 HELIX §. 20. 



distanlibus. — Diam. rnaj. 8, min. Vli^ alt. vix 3 miil. (Goll. 

 Nr. 137.) 



Helix perspectiva Say in Pliiiad. journ. I. 18 17. p. 18. 



— — (Hellcella) Fer. pr. 198. Hist. t. 86. f. 1. 



— — La7n. ed. Dh. 213. p. 130. 



— — Bi7in. in Bost. journ. III. p. 430. t. 21. f. 4. 



— — Chenm. ed. II. Helix N. 534. t. 85. f. 30 — 32. 



— pahda Desh. in Encycl. meth. II. N. 27. 

 Euryomphala perspectiva Beck ind. p. 9. 

 Patiila perspectiva Held in Isis 1837. p. 916. 



llabitat in America boreali, prope lacum Erie. 



262. H. striatella Anthony. '.'Ji.m.lfQjC^^t 



T, umbilicata, orbiculato-convexiuscula , tenuissinia, fusco- 

 cornea, confcrtim costulata; anfr. 4 vix convexiusculi, ultimus 

 basi inflatus, latiusculus; umbilicus majusculus, pervius; apertura 

 subcircularis ; perist. simplex , acutum , marginibus approximatis. 

 — Diam. maj. 6, min. Sy^, alt. 3 mill. (CoU. Nr. 138.) 

 Helix striatella Anth. in Bost. journ. III. p. 278. t. 3. f. 2. 



— — Binn. in Bost. journ. III. p. 432. 



— — Gould report p. 1 78. f. 112. 



— — Chemn. ed. II. Helix N. 535. t. 85. f. 36 — 38. 



— perspectiva Fer. hlst. t. 79. f. 7. 



Mabitat in America boreali: Ohio, Massachusetts , Vermont. 



Ohs. Diflerl ab H. perspectiva tesla minore, convexiore, anfractibus ma- 

 gis inaequalibus, umbilico angustiore et apertura subcirculari. An nihilominus 

 ejus varielas minor? 



263. H. Belcheri Pfr. 



T. late umbilicata, depressa, tenuis, diapbaha, superhe con- 

 fertim costulato-striata, subtus sublaevigata , nitida, concolor 

 corneo-cerea ; spira vix convexa; anfr. 5 vix convexiuscuH , ulti- 

 mus basi subplanulatus ; apertura obliqua, lunato-ovalis; perist. 

 simplex, acutum. — Diam. maj. 8 '/3, min. 7, alt. 4 mill. (Mus, 

 Cuming. ) 



Helix Belcheri Pfr. in Proc. Zool. Soc. 18 43. p. 12 8. 

 Ilabitat . . . ? (Ex itinerc Belcheri.) 



263*. H. gradata Gould. + 



T, parva, planorboidoa , tenuis, nitida, rufo-viridis, luteo ra- 

 diatiin variegata, supra depressa, infra acetabuliformis ; spirae 

 anfr. 5 convexi, intra umbilicum angulati, oblique et confertim 

 striali , striis inlerruptis volventibus decussati, ullimus subangu- 

 latus, versus apcrturam deflexus; sutura canaliculala; apcrlurit 



