206 HELIX-CATHAICA. 



High Mountains of theprov. Dshyli, west of Pekin, China, at alti- 

 tudes not less than 1000 meters. 



Helix pekinensis DESH., Bull, des Nouv. Arch, du Mus., ix, p. 

 13, t. 3, f. 13, 14, (1873); L c. x, p. 88, (1874). H. (Cathaica) 

 pekinensis MLLDFF., J. D. M. G. 1884, p. 342. Helix (Camena) 

 tchiliensis MLLDFF., Jahrb. d. m. Ges. 1875, p. 217. 



This shell is flatter than H. pyrrhozona, with wider umbilicus 

 and more oblique, smaller, aperture. Figures 65-67 represent the 

 tchiliensis Mlldff. Fig. 64 is an elevated form, called var. conoidea 

 Desh. 



H. MONGOLICA Mollendorff. PL 47, figs. 71-74. 



Shell umbilicated, depressed, obliquely costulate, and having a 

 crenulated carina ; dull gray-horn ; whorls 5, flat above, separated 

 by a superficial suture, the last whorl convex below, but little 

 descending in front. Aperture oblique, broad lunate, with a lip 

 within which appears yellow on the outside ; peristome white ; outer 

 margin straight above and horizontal, lower margin reflexed, a 

 little thickened within, columellar margin short, dilated, reflexed. 



Alt. 7-8, diam. 15 mill. (Mts.) 



Weitschang, northern part of Prov. Petscheli, near the Great Walt 

 under stones, alt. 1500 meters. 



H. mongolica MLLDFF., J. D. M. G. viii, 1881, p. 39, t. 1, f. 10. 

 MARTENS, Centralas. Moll. 1882, p. 13, t. 2, f. 14, 15. H. (Oath- 

 aica~) mongolica MLLDFF., Jahrb, 1884, p. 342. 



This species stands between H. pekinensis and H. plectotropis. 

 H. CONSTANTINO H. Adams. Vol. VI, pi. 32, figs. 54, 55. 



Shell umbilicated, depressed, thin, obliquely plicate, rufous- 

 brown ; spire nearly flat, the apex a little elevated, suture slightly 

 impressed, submargined. Whorls 5?, nearly plane, the last not 

 descending, compressed-carinate, the base convex ; umbilicus mod- 

 erate, profound ; aperture oblique, rounded-lunar ; peristome 

 expanded, pallid, margins converging, joined by a thin callus. 

 (Ad). 



Alt. 13, greater diam. 25, lesser 21 mill. 



Ichang gorge, China. 



H. constantinw AD., P Z. S. 1870, p. 378, t. 27, f. 8, 8a. 

 Evidently allied to the preceding species. 



