UNIVERSALITY DiST IB 7TED SPECIES. 77 



Lingual membrane (Plate VII, Fig". U) long and narrow, arranged 

 as in Patula. Morse gives 73 rows of 11-1-11 teetb, with 3 i^erfect lat- 

 erals. I counted 10-1-10, with 3 perfect laterals. Centrals with the 

 base of attachment long and narrow, expanded and notched at tehe 

 outer lower angles, narrowed above and retlected; reflection very small, 

 tricuspid, all the cusps bearing very short cutting points, the central 

 one, as usual, longest. Laterals with the base of attachment twice as 

 broad as in the centrals, the inner lower angle suppressed, notched at 

 the outer angle, broadly reflected above;' reflection larger than in the 

 centrals, with one inner, long, slender cusp, reaching nearly the lower 

 edge of the base of attachment, its cutting point quite reaching it, and 

 one small outer side cusp, also bearing a distinct cutting point. Margi- 

 nals low, wide, the reflection equaling the base of attachment and irreg- 

 ularly denticulated along its edge, the inner cusp the longest and bifid. 

 The dentition is quite that of Pupa, 



The above description is drawn from a specimen from Maine. The 

 European form is figured by Moquin-Tandon with a median projection 

 to the cutting edge of its jaw. Lehmann also figures a wide, slight 

 projection to the cutting edge. A comparison of the desc!iption and 

 figure of the dentition of the European specimens given by Thomson 

 and Lehmann shows no specific difference. It will be noticed that Leh- 

 mann's fljiure of the centrals shows a more developed reflection and 

 cusp and no side cusps. I believe, however, that careful comparison 

 will show no variation in this or other particulars. 



Vallonia piilchella, Muller. 

 Shell widely umbilicated, depressed, slightly convex fig. 39. 

 above, thin and transparent ; epidermis colorless ; whorls 

 4, very minutely striated, the last large and s^jreading at 

 the aperture like a trumpet; aperture orbicular, a little 

 dilated ; peristome much thickened, white, reflected, making 

 nearly a continuous circle, ends approaching; umbilicus 

 large, exhibiting all the volutions. Greater diameter 3, 

 lesser L'i"" ; height, li™'". ■*^- p^^'^'^heiia, 



■i ' » 7 z enlarged. 



Helix pulchella, Mitller, Verm., 30. — Pfeiffer, Mon. He]. Viv., i, 365. — Binney, 

 Bost. Joum. Kat. Hist., iii, S75, pi. ix, tig. 2 (1840); IVrr. MolJ., ii, 175, pi. 

 xvii, fig. 1.— Leidy, T. M. U. S., i, 256, pi. ix, figs. 7-9 (1851), anat.— Gould, 

 luvertebrata, 176, fig. 102(1841); ed. 2,429 (1870).— Adams, Vermont Mol- 

 lusca, 159 (1842). -AV. G. Binney, L. & Fr.-W. Sli., i, 157 (1869). 



HeVix minufa, Say, Joiini. Phil. Acad., i, 123 (1817) ; Nicb. Encycl., ed. 3 (1819) ; BiN- 

 NEY's ed. 3.— DeKay, N. Y.Moll., 40, pi. iii, fig. 33 (1843).— Morse, Am. 

 Nat., i, 544, fig. 39 (1867). 



