AMASTRA. 47 



ribs, at first rather coarse, becoming finer to the end of the 

 embryonic shell, which comprises 2^ whorls (fig. 7). Whorls 

 5y 2 > convex, the neanic whorls carinate, the keel usually 

 concealed in adult shells; the last whorl is swollen below the 

 deeply impressed suture, ventricose, tapering below. The 

 aperture is rather long and narrow, slightly oblique, white 

 within. Peristome slightly thickened close to the edge. Colu- 

 mellar lamella of moderate size, thin and spiral, white ; 

 parietal callus thin. 



Length 13.1, diam. 7.7, length of aperture 7 mm. 



Length 13.4, diam. 8.1, length of aperture 7.1 mm. 



West Maui: Mt. Helu. Cotypes in coll. Bishop Museum 

 and no. 108170 Acad. Nat. Sciences. Also in Mr. Thaanum's 

 collection. 



Amastra pilsbryi COOKE, Nautilus xxvii, Oct., 1913, p. 68. 



A. f rater no. Sykes of Lanai has some resemblance to this 

 species, being of stouter contour than other Heteramastras. 

 Although A. pilslryi has the stout contour and carinate, 

 costate embryo of typical Amastra, it is perhaps to be re- 

 garded as a stout species of Heteramastra, the wholly uu- 

 figured cuticle favoring this view. It is rather isolated in 

 the fauna as at present known, and does not readily fall into 

 any of the recognized groups. 



A. ELONGATA (Newcomb). PI. 2, fig. 18. 



Vol. XXI, p. 230. Three specimens are no. 29960 of the 

 Newcomb collection, Cornell University. One of these may 

 be the type which was said to be unique, but none agrees 

 exactly with Newcomb 's measurements. It is a shell having 

 the color and texture of A. subsoror, with which it agrees 

 in the long, convex embryonic whorls. The surface may be 

 a little rougher. It differs from subsoror in the decidedly 

 more elongate shape and consequently smaller aperture. It 

 differs from A. perversa by the longer, more convex em- 

 bryonic whorls. Seems to be a valid species, close to those 

 of Maui and Molokai. Length 10.9, diam. 5.2, aperture 4.4 

 mm. ; 614 whorls. 



