THE NAUTILUS. 45 



Nakamura, Oki. Types No. 95821, A. N. S. P., from No. 1567 

 of Mr. Hirase's collection. 



Kaliella okiensis, n. sp. 



The shell is perforate, conic, amber-colored, glossy, the spire conic 

 with slightly convex outlines, perifery thread-carinate, the base 

 convex. The surface is smoothish, above, with faint growth-lines, 

 and minute radial striae just below the suture on the intermediate 

 whorls; the base having faint spirals, not close together. Whorls 6, 

 convex, slowly increasing, the last having a narrow, thread-like 

 periferal keel. Aperture semilunar, rather narrow, the peristome 

 rather broadly dilated near the axial insertion. 



Alt. 2.7, diam. 3.6, mm. 



Nakamura, Oki. Types No. 95849 A. N. S. P., from No. 1568 

 of Mr. Hirase's collection. Also No. 1569. 



This species stands near K. sororcula, but it differs in having the 

 whorls crenulated below the suture on the spire. 



A NEW AMERICAN PLANORBIS. 



BY FRANK COLLINS BAKER. 



PLANORBIS BICARINATUS PORTAGENSIS n. var. 



Shell with the dorsal and ventral sides sharply carinated, the spire 

 and umbilicus typically forming deep, cone-like depressions ; sculp- 

 ture cf strong growth-lines and distinct spiral lines, as in bicarinatus 

 striatus ; aperture strongly auriculate, the upper and lower extremi- 

 ties forming a strikingly developed V-shape. 



Height 8.00, breadth 14.00; aperture height 10.00, breadth 5.50 

 mm. 



Height 8.00, breadth 13.00 ; aperture height 9.00, breadth 5.00 mm. 



Habitat : Portage Lake, on Fish River, Aroostook County, Maine. 

 (Collected by O. O. Nylander; types in collection of Chicago 

 Academy of Sciences.) 



This peculiar variety may be known by the strong keels on the 

 shoulder and base and by the V shaped upper and lower margins of 

 the aperture, which produce a notably auriculate aspect. It was at 

 first thought to be a form of Walker's variety major, but a compari- 

 son with specimens of the latter received t'rom the author shows that 

 the two are distinct varieties. 



