270 TERRESTRIAL AIR-BREATHING MOLLXJSKS. 



cus pervious ; aperture very oblique, lunate, ringent ; peristome slightly re- 

 flected, its terminations converging, joined by a triangular, tooth-like, two-forked 

 callus, the right-hand margin with one subvertical lamina, the 

 F 2iiJ£ 8 ' columellar margin with two acute denticles. Greater diameter 8, 

 lesser 7 mill. ; height, 4^ mill. 



Helix Hindsi, Pfeiffer, in Proc. Zool. Soc. 1845, 132 ; Mon. Hel. 



P. Hindsi. Viv., I. 416 ; in Chemnitz, 2d ed., I. 373, Tab. LXV. Figs. 7, 8. 



— Reeve, Con. Icon., 712 (1852). —Gould, in Terr. Moll., III. 



17. _W. G. BlNNEY, Ter. Moll., IV. 92, PI. LXXV1II. Figs. 5, 6, 8. — L. & 



Fr.-W. Sh., 93, Fig. 167 (1869). —Fischer and Crosse, Moll. Mex. et Guat., 



273 (1876). 



Dcedalochila Hindsi, Tryon, Am. Journ. Conch., III. 63 (1867). 



In the Texan Subregion in Texas and Mexico. 

 Animal not observed. 



Polygyra Texasiana, Moricand. 

 Vol. III. PI. XLV Fig. 1. 



Shell rimately perforated, depressed, orbicular, rather solid, of a pale horn- 

 color, sometimes with a revolving rufous band, with crowded rib-striaj above, 

 smooth, or faintly striated, and shining beneath ; spire nearly flat, of 5 whorls 

 separated by a well-marked suture, the outer one obtusely angular at periphery, 

 nearly at the plane of the spire, and somewhat deflected near the aperture ; 

 beneath convexly rounded, with a somewhat distorted appearance in conse- 

 quence of the whorl becoming narrower, rather than broader, towards the aper- 

 ture, leaving a minute umbilical perforation ; aperture very oblique, narrow 

 lunate, the peristome forming about two thirds of a circle, reflected, white, with 

 a constriction behind it, and armed with two denticles at its inner margin, one 

 near the centre, the other at the middle of the basal portion ; the extremities 

 of the peristome connected by a callus across the columella, of an acutely angu- 

 lar form, pointing to the middle of the portion of the peristome above the 

 upper denticle, the lower ramus of the angle being longest and largest, and a 

 little concave inwardly. Greater diameter 10, lesser 8^ mill.; height, 5 mill. 

 Helix Texasiana, Moricand, Mem. Soc. Phys. Hist. Nat. de Geneve, VI. 538, 

 PI. I. Fig. 2 (1833). — Deshayes in Lamarck, VIII. 133 ; ed. 3, III. 316 ; in 

 Fer. I. 74, PI. 1. c (excl. syn.). — Ferussac, Hist, des Moll., PL LXIX. D. 

 Fig. 2. — Pfeiffer, Mon. Hel. Viv., I. 418, excl. syn. and var. /3 ; Vol. IV. 

 318. — Chemnitz, ed. 2 (1846), I. 85, excl. var. and figure. — Reeve, Con. 

 Icon., No. 707. — Binney, Terr. Moll, II. 191, PI. XLV. Fig. 1. — W. G. BlN- 

 NEY, Terr. Moll., IV. 79. — L. & Fr.-W. Sh., I. 93 (1869). — Fischer and 

 Crosse, Moll. Mex. et Guat., 279 (1870). 

 Helix auriculata, Binney, Bost. Journ. Nat. Hist., III." 387. 

 Helix Tamaulipascnsis, Lea, Proc. Acad. Nat. Sci. Phila. 1857, 102 ; Journ. — ; 



Obs. XI. 139, PI. XXIV. Fig. 113. 

 Dwdalochila Texasiana, Tryon, Am. Journ. Conch., III. 62 (1S67). 



