AMASTRA, MOLOKAI. 255 



A specimen in U. S. Nat. Mus. (part of no. 117273), meas- 

 uring length 9, diam. 5 mm., aperture 4.5 mm., has a half- 

 open umbilicus intermediate in size between that of typical 

 petricola and umbilicata. It is rather solid, with the color of 

 petricola. 



67. A. ABAVUS n. sp. PI. 42, figs. 4, 5. 



The shell is imperforate, ovate-conic, very thick and solid, 

 rather glossy; fossil, and therefore without cuticle. Color 

 (1) first 21/0 whorls pale brown, next half whorl with brown 

 bands and white ground, last two whorls opaque white, or (2) 

 pale brown with white bands beginning on the penult, whorl, 

 predominating on the last whorl. Outlines of the spire a little 

 convex below, straight above, the apex obtuse. Embryonic 

 whorls convex, very finely striate, the first whorl nearly 

 smooth. Following whorls weakly convex with the usual 

 sculpture of fine growth-lines. Aperture small, indistinctly 

 angular at the base of columella; the outer lip very much 

 thickened within; columellar margin thick, bearing a small, 

 subhorizontal lamella; parietal callus very thick out to the 

 edge. 



Length 10.8, diam. 6.3, aperture 5 mm. ; 5% whorls. 



Length 11, diam. 6, aperture 5.1 mm. ; 5% whorls. 



Molokai : Pukoa, fossil. Cotypes to be deposited in Bishop 

 Museum, collected by Mr. D. Thaanum. 



This species is very closely related to A. petricola, from 

 which it is readily distinguished by the solid shell with very 

 thick lip, columella and parietal callus. 



Subgenus AMASTRA (p. 234). 

 Series of A. biplicata (p. 243). 



This series, otherwise Lanaian, has one species in central 

 Molokai. 



68. A. HUMILIS (Newcomb). PI. 40, figs. 7, 8. 



" Shell elongately conical, longitudinally rudely striate; 

 whorls 7, rounded above, flattened centrally; last one ob- 

 scurely carinated superiorly; suture deep, simple; apex acute; 



