240 COLUMELLA. 



In this species the first three whorls form a very obtuse, 

 convexly conic summit, the next two to three are equal in 

 diameter, and the last is expanded. The surface is like that 

 of typical C. edentula, being marked with very slight, irreg- 

 ular growth lines. The initial whorl is white, the rest pale 

 tawny in the loess specimens seen. One from Munich meas- 

 ures: length 2.75, diam. at last whorl 1.3 mm.; 6% whorls 



(fig. 1). 

 Benz appears to have had the name of this snail from Georg 



von Martens, who is quoted as authority for it by some 



authors. 



Widely spread in the Pleistocene, this species is now rare 



and discontinuous in distribution, being found in the eastern 



Alps and the far north. The recent form described as Pupa 



gredleri, does not appear to differ tangibly from the loess 



fossil. Clessin's account follows: 



Pupa gredleri Clessin (pi. 30, fig. 3). Shell cylindric, with 

 very short, obtuse summit, consisting of 7 to Ty 2 rather con- 

 vex whorls, the first two increasing very rapidly and forming 

 the short summit, the 3d, 4th and 5th almost wholly equal in 

 height and breadth, the last considerably higher and wider; 

 umbilicus very narrow. Shell in diameter somewhat narrower, 

 very finely striate, slightly glossy, distinctly translucent, of a 

 reddish-brown color. Aperture nearly rounded, lunate; peri- 

 stome blunt, scarcely expanded. Length 2.5, diam. 1 mm. 



In the upper forest and alpine region, in Switzerland 

 (Gemmi), in Tyrol, Campen near Bozen, Alpe Perdoi, on the 

 Schlern, on the Tristenstein, in the Tauferstal, on the Peitler 

 Kofel and the Franzenshohe. 



This species stands nearest to the diluvial P. columella 

 Benz, which agrees with it generally in form; it differs from 

 that by the smaller diameter and the somewhat smaller size. 

 It differs from edentula by the more slender form, greater 

 length and the considerably predominating last whorl. 



5. Columella inornata (Michaud). PI. 30, fig. 4. 



The shell is long, cylindric, very delicately striate, pellucid, 

 umbilicate, fulvous ; whorls 8, convex ; suture rather deep ; 

 aperture semilunar, toothless; peristome subreflected ; apex 

 obtuse. Length 2 lines, diam. % line. 



