40 THE NAUTU.LS. 



above which only the tilted edge of the last volution projects. Post- 

 nuclear whorls well rounded, moderately contracted at the sutures and 

 appressed at the summit, which falls in the middle of the peripheral 

 sulcus. Periphery of the last whorl somewhat inflated, marked by a 

 moderately deep sulcus, which is bounded on each side by a slender 

 raised thread. Base short, well rounded, with a moderately broad 

 umbilicus. Entire surface of spire and base marked by strong lines 

 of growth and numerous fine spiral striations. Aperture large, 

 rhomboidal ; posterior angle obtuse; outer lip thin; columella slender, 

 curved and revolute, provided with a strong fold at its insertion. 



The type is in the Winkley collection, and comes from Woods 

 Holl, Mass. It has seven post-nuclear whorls and measures, length 

 3.2 mm., diameter 1.6 mm. 



I take pleasure in naming this for Mr. Paul Bartsch, of the Smith- 

 sonian Institution, and wish to express my thanks to him and Dr. 

 Dall for their help on this and other species. 



Mr. Bartsch writes concerning the above: "The single specimen 

 is a most interesting one; it represents a group (^SnJcoriveUa) not 

 heretofore reported living." 



A NEW CABIinFEX FItOM THE SANTA CLABA LAKE BEDS (PLIOCENE), 



CALIFOBNIA. 



BY HAROLD HANNIBAL. 



Carinifex SANCT^CLAR^ n. sp. 



Shell small (for the genus), heavy, subglobular; spire depressed ; 

 whorls three, inflated, subcarinate at outer margin above, from which 

 the shell slopes concavely upward to a raised ridge bordering a nar- 

 row, rather deep sutural groove. Umbilicus narrow, marked off by 

 a sharp carina; lip complete, semilunar, full, reflexed below. Shell 

 marked by moderate, diagonal growth-lines, occasionally raised into 

 coarse ridges. Alt. 5 mm., lat. 8 mm. 



Type locality: Near Los Gatos Limestone Quarry, Los Gatos, 

 Santa Cruz Mts., Cal. 



This species is easily recognized by the concave upper surface of 

 the whorls. It varies somewhat in size, some specimens being twice 

 as large as the type, which is probably just mature. 



It and Amnicola yatesiana J. G. C. are the two characteristic 



