BULIMULUS-ORTHOTOMIUM. 129 



Aperture about half the shell's length, ovate, corneous and white 

 inside, the peristome acute, unexpanded, generally slightly thick- 

 ened, or with a rib within. Columellar margin dilated. Columella 

 regularly concave. Alt. 20, diara. 11-12, alt. of aperture 10-11 

 mill. 



Southwestern North Carolina; Henry and Lawrence Counties, 

 Kentucky ; ivest to Camden Co., central Missouri, and Shawnee Co., 

 Kansas; southwest to Alabama and Corpus Christi, Eagle Pass and 

 Pecos Co., Texas. 



Helix dealbata SAY, Journ. Acad. N. S. Phil., ii, p. 159 ; Binney's 

 edition, p. 10. Bulimus dealbatus POT. et MICH., Galerie, i, p. 139, 

 t. 13, f. 3, 4. PHIL., Abbild., i, p. 158, t. 2, f. 6. KUSTER, Couchyl. 

 Cab., 1. 16, f. 11-13- PER., Monogr., ii, p. 187 ; Conchyl. Cab., p. 55. 

 KEEVE, Conch. Icon., f. 455. BINNEY, Terr. Moll, p. 276, pi. 51, f. 

 1 ; pi. 51a, except upper and lower figures. LEIDY, Terr. Moll. 

 i, p. 229, pi. xv, f. 1 (anatomy). W. G. BINNEY, Terr. Moll., 

 iv, p. 130, pi. 80, f. 6, 7 ; Land and Freshwater Sh. N. A., i, p. 

 208, f. 35S.Bulimulus dealbatus W. G. B., Terr. Moll., v, p. 393, f. 

 269 (jaw) ; pi. x, f. E (teeth), and Man. Amer. L. Sh., p. 401, f. 441. 

 CROSSE & FISCHER, Moll. Mex., i, p. 566. STEARNS, Proc. U. S. 

 Nat. Mus., xiv, 1891, p. 97 ; xvi, 1893, p. 751. SAMPSON, Nautilus, 

 viii, p. 18. SINGLEY, Texas Moll., in Fourth Ann. Rep. Geol. Surv. 

 Texas, p. 309. SIMPSON, Proc. U. S. Nat. Mus., xi, 1888, 452. Scu- 

 talus dealbatus Say, TRYON, Amer. Jour. Conch., iii, p. 173, pi. 14, f. 

 9. Buliminus dealbatus BECK, Index, p. 72. Zebrina dealbata 

 HELD in Isis, 1837, p. 917. Bulimus liquabilis REEVE, Conch. 

 Icon., f. 387, pi. 57. Bulimus confinis REEVE, Conch. Icon., pi. 86, 

 f. 643. 



Figures 28 and 30 represent the typical forms of this species, as 

 developed in the region from Tennessee and Alabama to Kansas 

 and northern Texas. In the latter state the shell becomes larger 

 (figs. 1, 19, from Waco) and often of stouter figure with larger 

 mouth (figs. 27, 29, 48, Lee Co.), while retaining the texture. The 

 apical whorls of these are more strongly ribbed. 



Var. RAGSDALEI Pilsbry. PI. 18, fig. 31. 



Like typical dealbatus in contour or more slender. Entire sur- 

 face sculptured with sharp, thread-like, obliquely longitudinal strice ; 

 the stride white, spaces gray or pinkish-gray. 



Alt. 21, diam. 10'3, length of aperture 9'7 mill. 



Alt. 20, diam. 11, length of aperture 9'5 mill. 

 9 



