North American Helicidm. 19 



This species has, like P. faUgiata Say and P. 2)Ucata Say, one large 

 tooth on the left lip, and two smaller ones on the right lip. It differs 

 from the first -in not being carinate, from the last in being larger, and 

 having larger strice. In the Dorfeuilliana the tooth on the left lip is 

 large and square, with an indentation in the centre. The view into the 

 mouth is nearly obstructed by the teeth, leaving, to appearance, three 

 nearly square apertures. The superior part of the shell is striate, while 

 the inferior part is nearly smooth, and exhibits two volutions. I have 

 seen but a single specimen, which, I believe, is the only one obtained 

 by Mr. Dorfeuille, who obligingly sent it to me." 



I have already mentioned that Binney, both in the Boston 

 Jl. and Terr. Moll., treats this species as identical with fatigi- 

 ata Say, iMcata Say, and Troostiana Lea, and that Deshayes 

 confounds it with the two former. 



Lea's Dorfeuilliana is certainly not described in Pfeiffer, 

 Chemnitz (ed. 2), or Reeve, nor is there any figure of it in the 

 two latter works. In all of them Honduras is erroneously 

 given as one of the habitats, and I believe that they describe 

 and figure the Honduras species, referred to by Shuttleworth 

 (Diag. N. Moll. p. 16), in the following terms : — 



"Helix dysoni. 



" T. late et subperspective umbilicata, depressa, nitida, rufo-cornea, 

 superne brevissime conoidea, plicato-striata, subtus inflata, striis exilio- 

 ribus subobsoletis, lineisque paucis interruptis spiralibus circa umbilicum 

 impressis obscure notata ; anfr. 5 J, convexiusculi, lente accrescentes, 

 ultimus vix descendens, angulatus ; sutura profunda ; apertura majus- 

 cula, auriformis, tridentata : dente 1, valido, obliquo, pliciformi, in 

 pariete aperturali intrante ; perist. reflexum, album, dentibus 2 margina- 

 libus intus munitum. 



^^ Syn. Helix Dorfeuilliana Pfr. 1. c. p. 410, No. 1067, non Lea. et 



excl. fig. Fer. 

 « « Chemn. ed. 2, t. 65, fig. 25-28. 



