BULIMULUS-ORTHOTOMIUM. 143 



Conchyl., 1895, p. 137, pi. 7, f. 6, 6a, 6b (living animal). COOPER, 

 Zoe, iii, p. 15 ; Proc. Cal. Acad. (2), iii, pp. 101, 208,210. Bulim- 

 ulus (Mesembrinus) pallidior BINN. & BLD., L. and Fr. W. Sh. N. 

 A., i, p. 195, f. 340, 341. Thaumastus pallidior TRYON, Amer. 

 Journ. Conch., iii, p. 170, pi. 13, f. 9. Bulimulus (Scutalus) pallid- 

 ior CROSSE & FISCHER, Moll. Mex., i, p. 512, pi. 20, f. 9. BALL, 

 Proc. U. S. Nat. Mus., xvi, 1893, p. 640, pi. 72, f. 2, 3. STEARNS, 

 Proc. U. S. N. Mus., xvii, p. 164. Bulimus vegetus GLD., Journ. 

 Bost. Soc. N. H., vi, 1853, p. 375, pi. 14, f. 2 ; Otia Conch., p. 184. 

 PFR., Monogr., iv, p. 397. Bulimulus (pallidior f} vegetus 

 COOPER, Proc. Cal. Acad. (2), iv, p. 133, pi. 5, f. 2, 3, with var. 

 vegexpiza, p. 134, pi. 5, f. 1 ; pi. 6, f. 27. Mesembrinus pallidior 

 W. G. BINNEY, Ann. N. Y. Acad. Sci., iii, p. 122 (dentition). 



The specimens reported from Costa Rica are a species of Drymceus, 

 showing a remarkable resemblance to this Bulimulus. 



Var. striatulus Dall. PI. 19, figs. 50, 52, 68. 



Surface finely but strongly granular from the persistence of spiral 

 incised lines cutting close longitudinal wrinkles. Lip broadly re- 

 flexed and recurved throughout ; columellar fold conspicuous within. 



Carmen and Margarita Islands; Gulf coast of the Peninsula, 

 and on the Sierra el Taste and Sierra Laguna. 



Figure 52 represents Cooper's variety vegexpiza, which is identical. 



B. ACHOLUS J. Mabille. 



Shell nearly covered rimate-umbilicate, conic ovate, solid, rather 

 thick, subopaque ; gray, covered with a caducious dull rufous cuticle 

 and sparsely marked with pale brown streaks ; longitudinally stri- 

 ate, and everywhere with compressed scattered granules. Whorls 

 5, irregularly (the first moderately, the rest rapidly) increasing, con- 

 vex, the last whorl much inflated, depressed toward the well im- 

 pressed suture, attenuated at base, slightly descending at the apert- 

 urej nearly equalling a half of the shells length. Aperture ovate, 

 rather ample, vertical ; peristome acute, slightly thickened, patul- 

 ous, whitish ; margins approximating, the outer a little arcuate, col- 

 umellar dilated over the umbilicus. Columella slightly oblique, 

 arcuate. Length 46, greatest diam. 21 mill. ; aperture with per- 

 istorae 27 mill, long, 18 wide. (Mabille}. 



Mountains of Lower California, in company with B. montezuma. 

 (Diguet). 



