EASTERN PROVINCE — SOUTHERN REGION SPECIES. 375 



obtaiued from Mr. Dorfeuille some facts concerniDg the original dis- 

 covery of tliis species, which prove beyond all doubt that it was acci- 

 dentally brought from Kentucky. Jt is not an inhabitant of Ohio. 



P. DorfeuilUana differs materially in its characters from the allied 

 species; the striaj on the upper surface are not so well defined as in 

 Troostiana, but more so than in Hazardi, while the base is more smooth 

 than in either of them, having only very delicate stride, with micro- 

 scopic impressed spiral lines. The parietal tooth is quadrate ; the two 

 teeth on the peristome are more nearly of the same size and form than 

 in fastigans and Troostiana. In this species the inferior tooth is trans- 

 verse, and in some specimens broader than the superior one, but has a 

 somewhat pointed apex ; both are very neatly equally deeply seated, 

 but so far apart as to allow a view between them into the aperture, 

 leaving, as Mr. Lea expresses it, "to nppearance three nearly square 

 apertures." Say would have described the two teeth as " separated by 

 a remarkable sinus." The peristome of this is more thickened and less 

 reflected than in the other species; behind it is deeply constricted, 

 without any appearance of pits showing the position of the teeth 

 within. 



There is a form of DorfeuilUana which differs from the tyj^e in that 

 the superior tooth on the peristome is larger and more deeply seated 

 than the inferior one, and that the latter, though more developed, is 

 much of the same form as the inferior tooth in fastigans and Troost- 

 iana. The parietal tooth partakes of the general character of that in 

 Lea's type of DorfeuilUana, but its lower and terminal margins project 

 more perpendicularly from the parietal wall. The umbilical perfora- 

 tion is also larger and the base of the shell is more smooth. The fol- 

 lowing are the measurements of a large specimen : Greater diameter 9, 

 lesser 8"""; height, 4""". I am much inclined to consider this a dis- 

 tinct species, but remark upon it, as I believe it is more commonly found 

 in cabinets under the name of DorfeuilUana than the shell described 

 by Lea. It is called var. Sampsoni by Wetherby. 



P. DorfeuilUana, and also the shell last considered, have a tubercle 

 within the aperture very similar to that in fastigans and Troostiana. 



Jaw not observed. 



Lingual membrane with 20-1-20 teeth, the tenth liaving its inner 

 cutting point split. Marginals as usual in the genus. (Terr. Moll., V, 

 Plate VI, Fig. I.) 



Genitalia unobserved. 



