VALLONIA. 257 



To this species I also refer some quaternary fossils collected by 

 the Texas Geological Survey, in a Dry Salt Lake near Eddy, South- 

 ern New Mexico, and two specimens found in Osborn's Julia Canyon, 

 N. W. Texas, at either place in company with a number of small 

 land and fresh-water mollusca embedded in a fine quartz sand. 



Whether these mollusca, which evidently range under the same 

 head, are really identical with the V- gracilicosta of Reinhard, I am 

 unable to decide at present, but from the description, believe so. 



V. PATENS Reinhard. Unfigured. 



Shell small, flat, with scarcely projecting apex, with very wide 

 perspective umbilicus ; grayish-white. Whorls 3 J, somewhat 

 depressed, moderately increasing in width, separated by a deeply 

 impressed suture, and with distant membranous ribs; the last 

 scarcely descending toward the aperture. Aperture very oblique, 

 transversely oval, with everted but scarcely thickened .peristome; 

 upper margin almost straight, lower margin symmetrically curved, 

 insertions of the margins approximate. Diam. 2, alt. scarcely 1 mill. 



V. patens REINH., Sitzungsber. Naturf. Fr. Berlin, 1883, p. 43. 



This species reminds one of H. costata .as to the ribs, but differs 

 from it by its smaller size, wider umbilicus and more oblique aper- 

 ture, with slightly thickened peristome. It has been found, by Dr. 

 O. v. Moellendorff, on the Powantschan, Prov. Chili, China, in com- 

 pany of H. tenuilabris A. Br., a species which seems to be widely dis- 

 tributed in northeastern Asia, while in Central Europe it is only 

 found fossil in the pleistocene loess. This fact corresponds in an 

 interesting way with the results of Nehring's investigations upon the 

 vertebrate fauna of the loess. The original description is translated 

 above. 



(4) Group of V. cyclopliorella Anc. 



Aperture with margins approximate, transversely ovoid or pear 

 shaped, without (or with a thin) lip ; surface densely striate or rib- 

 bed ; last whorl ascending before descending in front. 



V. PERSPECTIVA Sterki, n. sp. PI. 33, figs. 39, 40, 41, 42, 43, 44, 45 



Shell very widely, perspectively umbilicated, fiat or little elevated 



above; pale horn color or colorless, thin, translucent, with rather 



dense, rather regular, moderately strong membranous ribs, and finer 



strise between them ; nucleus without revolving lines (?). Whorls 



3i, gradually increasing, a little flattened below the periphery, with 



17 



