204 



LAND AND FRESH-WATER SHELLS OF N. A. [PART I. 



Btdimulus schiedennus. 



Blllillllllus SClliedeaillls, Pfeiffer. — Shell perforated, ovate- 

 acute, calcareous, white, with irregular longitudinal wrinkle-like stria) ; 

 whirls sis and a half, rather convex, the last as long as the spire ; aper- 

 ture oval - oblong, brownish 

 Fig. 352. within ; columella obsoletely 



folded ; peristome simple, 

 acute, its margins joined with 

 a shining callus, the colu- 

 mellar one broadly reflected, 

 white and shining. Length 

 31, diam. 17 mill. ; length of 

 aperture 17, breadth 9. 



Bulimus schiedeamts, Pfeif- 

 fer, Syrab. ad Hel. Hist. 

 I, 43 ; Mon. Hel. Viv.' II, 187 ; in Chemnitz, ed. 2, no. 2U;, pi. xlvi, 

 f. 3, 4 (1854).— Philippi, Icon. I, 3, p. 56, pi. 1, f. 12 (1843).— Reeve, 

 Con. Icon. no. 361.— W. G. Binney, Terr. Moll. IV, 129. 

 Bulimus alternatus, Binney, Terr. Moll. pi. li, f. 2. — Not of Say. 

 Thaumastus schiedeanus, Tryon", Am. Journ. Conch. Ill, 172, pi. xiv, f. 12 



(1867) 

 Texas and the neighboring part of Mexico. Teiy common in 

 Washington County, Texas. 



From Buliimdus alternatus this species is distinguished by a 

 rougher surface, a light-colored aperture, a shorter and more 

 pyramidal spire, and by the want of the highly developed tooth- 

 like fold upon the columella. It is of a dead white color, not 

 variegated with brown blotches. The aperture is shorter and 

 wider, and there is no strong internal white thickening to the 

 peritrerae. Like all the species of the group it has a highly 

 polished very light waxen apex. There are sometimes light deli- 

 cate waxen vittsB upon the first two whirls. 



No description of this species was given by Dr. Binney, nor 

 was it figured unless in plate 51, fig. 2, as B. dealbatus, var. 

 On p. 278 of vol. 2, Dr. Grould erroneously refers to it pi. 51b. 



' Pfeiflfer quotes also as synonyms the manuscript names B. xantliostomus, 

 Tv'jegm., and B. candidissimus, Nyst. 



