Neiv Species of Atnastra. ii 



auy iudication of a light zone below the sutures. Spire with con- 

 vex outlines, blunt. Embryonic whorls large, rounded, smooth, 

 the first increasing rapidly, flattened above. The post-embryonic 

 whorls are slightly convex, roughly sculptured with coarse, slightly 

 oblique, irregular growth-wrinkles, and on the last two whorls 

 encircled by numerous faint spiral striae, the surface appearing 

 under a strong lens to be minutely pitted ; the last whorl cylin- 

 drical, tapering very gradually towards the base. The aperture 

 is oblique, narrow, its outer margin furnished with a strong thick 

 and blunt lip-rib. The columella is not as short as in A. anthoni, 

 narrowly triangular, thick-callus. The columellar fold is low, 

 blunt, diagonal, nearly basal in position and extends nearly to 

 the margin of the columella. 



Length 18.0, diam. 9.3, apert. 8.2 mm.; 6 whls. (Holotype) 

 " 18.9, " 9-3, " 8.0 " bVz " 

 17.5, " lo.o, " 8.4 " 6 



Kauai : Pleistocene deposits of the southwestern bluff of 

 Kalalau valley about 100 feet elevation (Knudsen and Cooke). 



Holotype and coty pes No. 41,996, paratypesNo. 15,657, Bishop 

 Museum. 



A . rcmota is undoubtedl)- closely related to A . ayithoni. It dif- 

 fers from Newcomb's species by its much larger and flatter embry- 

 onic whorls, more cylindrical and less conic outlines. There is no 

 doubt that both species are derived from the same stock as the 

 granular surfaces of both are almost identical though slightly 

 coarser in the best preserved specimens of A. reniota. In two 

 specimens of this species, the aperture is very oblique and narrow, 

 the last whorl descending very rapidly just before terminating at 

 the peristome. 



A. rugulosa var. fastigata, n. var. 



PL B. Fig. I. 



The shell is minutely perforate or imperforate, dextral. long- 

 conic, nearly solid, in its fossil state of a pale bluish-white. The 

 spire is conic, with nearly straight outlines, pointed at the apex. 

 The embryonic whorls are extended, convex, nearly smooth, 

 polished. The rest of the whorls slightly convex, irregularly 

 finely sculptured with rather close growth-wrinkles ; the last sub- 



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