HELIX. 69 



Binney erroneously quotes Say as describing obstricta with 

 only one tooth on the outer lip. 



The species is found fossil in the Postpleiocene at 

 Natchez, and recent in Ohio and Tennessee. 



HEIilX APPRESSA Say vol. ii. p. 140, pi. xiii. 



Helix appressa Say (Biiiney's ed.) 15. 

 Pfeiffer, 1. c. iii. 267. 

 Reeve, Con. Icon. No. 689, (1852). 

 Desha YES in Fer. 1. c. i. 141. 

 Helix Unguifera Deshayes, in Lara. 2d ed. viii. 70; 3d ed. lii. 293. 

 Pfeiffer, Symb. ad Hist. Hel. p. 19, (ahsq. desc.) 

 Chenu, 111. Conch, pi. xii. fig. 5. 

 Delessert, Recueil, pi. xxvi. fig. 5. 



I have received from Illinois large quantities of Say's 

 var. a. of this species, collected by Mr. R. Kennicott. It is 

 thus described by Say: — " Labrum with two projecting 

 angles." 



HELIX INFLECTA Say vol. ii. p. 143, pi. xlv. fig. 3. 



Helix inflecta Say (Binney's ed.) p. 16. 

 DeKay, N. Y. Moll. p. 45. 



Mrs. Gray, Fig. Moll. An. pi. 193, fig. 7. (Ex. Host. Jour. absq. 

 descr.) 

 Helix clausa Deshayes in Lam. 3d ed. 3, 309; in Fer. Hist. 1. c. i. 143. 

 Reeve, Con. Icon. No. 704, (1852). 

 Pfeiffer, 1. c. iii. 269. 

 Xolotrema clausa Rafinesqce, Enumeration, &c. p. 3, (1831). 



The young of this may, perhaps, be H. porcina Say 

 (vid. H. hirsuta). 



Pfeiffer mentions a Texan variety, smaller, " umbilico 

 non omnino clauso." 



It is a typographical error on p. 33, vol. iii. to call this 

 H. triodonta Jahn. 



Rafinesque thus describes Xolotrema clausa, " Subde- 

 pressed, 5 spires a little striated, opening almost hidden." * 



* It is frequently argued that the descriptions of this author are indefinite. To 

 do justice to him one should pay attention to his remark, that if one does not 

 admit his generic distinctions " it would be requisite to repeat, in the descriptions 

 of their specific characters, that of the characters of my new genera, which would 

 render the definition of the species prolix." Tr. of Mon. p. ii. 



