IIELIX §. 76. 409 



llelix poly(j\jrata Binn. in Bost. journ. III. p. 391. t. 19. f. 4. 

 Polygyra septemvolva Say \u Plulad. journ. I. P. 2. 1818. p. 278.*) 



— — Soto. Conch. Man. ed. II. p. 234. f. 275. 276? 



— planorhula Beck ind. p. 23. 

 Ilabitat in America boreali : Georgia , Florida. 



1064. H. volvoxis Parreyss. 



T. unibilicata, orbicalato-convexa, tenuis, rufo-cornea, pel- 

 lucida, regulariter costulato-striala; spira brevissima, convexa; 

 anfr. 7 convexi, regulariter accrescentes, ultimus reliquis supernc 

 vix latior, angulatus, infra angulum inflatus, striatus, nitidus; 

 umbilicus latus, regularis, anfractu ultimo latissimo, reliquis rc- 

 gulariter decrescentibus; apertura majuscula, reniformis; perist. 

 intus callosum, reflexum. marginibus callo brevi, triangulari, den- 

 tiformi junctis. — Diam. maj. 9, min. 8, alt. 4 mill. (Coll. Nr. 644.) 

 Helix volvoxis Parr. in schod. 



— — Pfr. Syrab. III. p. 80. 



— — Chemn. ed. II. Hehx N. 393. t. 06. f. 4 — 6.^ 

 Polygyra septemvolva Beck ind. p. 23? 



Ilabitat in America boreali: Georgia, Florida. 



Obs. Hanc speciem, a praecedente lolo coelo diversam, saepius ex Anje- 

 rica nomine H. seplemvolvae Say accepiraus. 



1065. H. microdonta Deshayes. 



T. umbiiicata, orbiculato-plana, coi^nea vel pallide rufescens, 

 superne plana, oblique et argutc striata, subtus convexa, tener- 

 rimestriata, nitida, maculis opacis radiantibus notata, umbilico 

 infundibuliformi excavata; anfr. 6, ultimus ad aperturam gibbus; 

 apertura subtriangularis; perist. subincrassatum, reflexiusculum, 

 marginibus dente calloso, triangulari junctis. — Diam. maj. 9, 

 min. 8, alt. 3 '/2 mill. (Gofl. Nr. 645.) 



Helix microdonta Desh. in Fer. liist. p. 6. t. 72. f. 13.**) 



— — Chemfi. ed. II. Helix N. 395. t. 66. f. 10 — 12. 



— plana Dunker in Phil. Icon. I. 3. p. 51. t. 3. f. 1 1. 



Habitat in insulis Bermudis et in Texas (teste coll. Menkeana). 



Obs. Differt a sequente spira plana, anfraclibus subtus magis evolulis, 

 minus inflatis, umbiiico extus dilatato, perist. subincrassato , dente majoro pa- 

 rietis aperluralis. 



*) Yerba descriplionis Sayanae: «beneath the four exterior volutions 

 oqually prominont, transverse diameters equal to those of the upper surface; 

 umbilicus central, moderate, attcnuated to Uie apex so as to exhibil the remain- 

 ing volulions», ad speciem nostram non omnino quadrant. 



**) T. discoidea , planulata , albo-grisea, flammulis obhquis fuscis subru- 

 bescentiJjusve ornala; superne spira depressissima , sublus profunde lateque 

 in ambilu umbilicala , tenuissime et regulariler striata ; apertura obliqua , mar- 

 ginala. ovato-semilunari; labro dente obliquo , minimo praedito. (Desh. 1. c.) 



