AMASTRA, OAHU. 187 



Series of A. cornea. 



Acutely or acuminately ovate Amastras, with the spire 

 slender, attenuate, being more or less contracted near the 

 apex; embryonic whorls very finely striate vertically and 

 usually with traces of spirals (pi. 31, fig. 12). Cuticle thin, 

 persistant, the last whorl without a dull outer or deciduous 

 coat. Columellar lamella subhorizontal. 



Rather small, long-spired derivatives of the reticulata 

 series, two species occurring in the Waianae range, two others, 

 rare and local, in the eastern range. 



It is quite possible that the eastern species are divergent 

 forms of the reticulata series, related to transversalis, textilis, 

 irwiniana, etc., and not directly allied to those of the Waianae 

 range. I am unable to settle this point. 



Key to Species. 



a. Lip strengthened by a strong white internal rim; spire 

 brown, the last whorl opaque- whitish, often malleate ; Wai- 

 anae range. A. crassilabrum, no. 32. 

 a 1 . Lip thin or very slightly thickened. 



6. Spire rapidly tapering from the last whorl. 



c. Shell brown, or with the last whorl pale ; pari- 

 etal callus thin; Waianae Mts. 



A. cornea, no. 31. 



c 1 . Shell olivaceous; parietal callus thick; east- 

 ern range. ' A. (emulator, no. 34. 

 6 1 . Penult, whorl rather large, the spire wider below; 

 fossil, eastern range. A. subcornea, no. 33. 



31. A. CORNEA (Newcomb). PI. 31, figs. 9, 10, 12, 13, 14. 



' ' Shell irregularly, acutely conical, the apex pointed ; last 

 whorl inflated ; thin, corneous, with minute longitudinal striae ; 

 whorls 7, rounded; aperture subovate; lip thin, translucent; 

 columella straight, white, and armed with a transverse plaited 

 tooth. Color uniform dark horn, columella and tooth white. 

 Length ten-twentieths, diam. five- twentieths of an inch. Hab- 

 itat 1" (Newc.}. 



Oahu: Lihue (Gulick) ; below Kaala (Perkins) ; Kaala and 



