UNIVERSALLY DISTRIBUTED SPECIES. G9 



The elevated form only is figured liere. It is interesting to state 

 that in Europe also these two extreme forms are known to exist, the 

 analogue of egena being called Mortoni (Jeffreys). 



The plane of the base is so nearly horizontal that the shell, when set 

 upon its base, is upright. It is so transparent that some of the sutures 

 of the spire are visible through the substance of the shell, when viewed 

 on the base. 



There is a variety with an internal tooth. 



Jaw arcuate, ends attenuated; anterior surface fig^t. 



smooth ; concave margin smooth ; with an obtuse me- 

 dian projection. 



_ . - , -^ . _,, ,. ^ ^ - ^^ Jaw of Z.fulvus. 



Lingual membrane : Morse gives 80 rows ot 18-1-18 (Morse.) 



teeth, with 7 laterals on either side. The specimen examined b}" me 

 (from Orono, Maine) has 30-1-30 teeth, Avith 8 perfect laterals. This 

 difference in the number of the marginals is unusual for two individ- 

 uals of the same species. 



The peculiarity of the lingual is the bifurcation of all the marginal 

 teeth. On Plate II Fig. E, of T. M., V., I have drawn one central with 

 its adjacent lateral, and one marginal extracted from a Maine specimen. 



By the bifurcation of the marginals this species is allied to Vitrino- 

 conus (Semper, Phil, Archip.); also Z. Gwidlaelii^ which, however, has 

 some of its marginals even tricuspid, and tricuspid laterals. 



HELICIDiE. 



PATIJL.A. (See below.) 

 Patula striatclla, Anthony. 



Shell umbilicated, orbicularly convex, thin, brownish horn- ^J^^^- 

 color, with crowded ribs; whorls 4, scarcely convex, the last in- 

 flated below, rather wide; umbilicus large, pervious; aperture 

 sub-circular; peristome simple, acute, its terminations ap- 

 proached. Greater diameter G™'", lesser 5i'""^; height, 3™™. p.lu^Ma. 



Helix striatelJa, Anthony, Bost. Jourii. Nat. Hist., iii, 278, pi. iii, fig 2 (1840). — 

 BiNNEY, Bost. Joiirn. Nat. Hist., iii, 432, pi. xxi, fig. 5 (1840); Terr. Moll., 

 ii, 217, pi. 5XX, fig. 2.— Gould, Invert., 178, fig, 112 (1841).— Adams, Ver- 

 mont Mollusca, 162 (1842).— DkKay, N. Y. Moll., 43, pi. iii, fig. 40(1843). 

 —Chemnitz, 2d. ed., ii, 115, tab. Ixxxv, figs. 30-38.- Pfeiffer, Mou. Hel. 

 Viv., i, 104.— Reeve, Con. Icon., 727 (1853).— W. G. Binney, T. it. MuJi., 

 iv, 99. — Morse, Amcr. Na'., i, 545, fig. 40 (1807).- W. G. Binni.y, L. & 

 Fr.-W. Sb., i, 80, fig. 140 (1869).— GouLD and Binney, Inv. of Mass., ed. 2, 

 413 (1870). 



