10 LEPTACHATINA. 



Length 9.3, diam. 5 mm. 



Length 9.2, diam. 4.4 mm. 



Oahu : Kawaihapai, on a steep wooded bluff, about 500 ft. 

 above the coastal plain, and perhaps % mile from the sea. 

 Cotypes No. 110593 A. N. S. P. and in Bishop Mus., coll. by 

 Cooke and Pilsbry, 1913. 



Leptachatina cookei PILS., Nautilus, xxviii, p. 61, October, 

 1914. 



This is a much larger, more robust species than other forms 

 having a parietal callus and posterior commissure, and the 

 columellar lamella is broader and less oblique. By its form 

 and texture it recalls L. resinula. 



No living shells were found, but the species cannot have 

 been long extinct. It may possibly turn up alive in some 

 part of the western end of the Waianae range. 



L. MICRODON P. & C., n. sp. PL 9, fig. 3. 



The shell is perforate, oblong-conic, opaque, light brown; 

 surface rather glossy, marked with fine growth-lines. Out- 

 lines of the spire straight in the upper half, where the whorls 

 are but slightly convex; the penultimate whorl more convex; 

 last whorl not very convex, compressed around the axial 

 crevice. Whorls 6%. The suture is but slightly impressed, 

 and in the last third of a whorl it ascends slightly, but it is 

 not deflexed at the aperture, as usual in related species. The 

 aperture is hardly oblique, ovate-piriform. The outer lip is 

 obtuse, whitish within. The face of the columella is strongly 

 calloused above, where it passes into the parietal callus. 

 Columellar fold is rather small and ascends obliquely. The 

 parietal callus is thin, transparent, bounded by a thickened 

 edge, which terminates above in a small, drop-like tubercle, 

 separated from the termination of the outer lip by a narrow 

 groove. 



Length 11.3, diam. 5 mm. ; aperture 5 mm. 



Oahu: western ridge of Popouwela, "Waianae Mountains, 

 Spalding, Cooke and Pilsbry, 1913. 



L. cookei is a shorter shell with more conic spire ; the aper- 

 ture is contracted; the columella is notably shorter, with a 



