184 AMASTRA, OAHU. 



thick border within the lip. The axis is rimate or imperfor- 

 ate. Specimens from Keawaawa measure : 



Length 13.2, diam. 6.1, aperture 5.8 mm. ; 6 whorls. 



Length 12, diam. 6, aperture 5 mm. ; 6 whorls. 



Length 12, diam. 6.5, aperture 5.2 mm. ; 5% whorls. 



Length 10.5, diam. 6.1, aperture 5 mm. ; 5% whorls. 



By its embryonic sculpture, coloration and the spiral in- 

 cised lines, this beautiful little snail is related to A. undata 

 Baldw. It is not very closely allied to A. reticulata Newc., 

 with which Newcomb united it. One of us (Hyatt) consid- 

 ered transversalis to belong to Amastrella, near ~brevis, pulla 

 and pusilla. Figured from Keawaawa examples. As the 

 type locality is unknown, we may consider this place as such. 

 It is said to be now extinct. 



28. A. CAPUTADAMANTIS n. sp. PL 30, figs. 19, 20. 



The shell is cylindric-oblong, rather thin, the penultimate 

 whorl nearly equal to the last in diameter ; spire consequently 

 bulging below, then rapidly tapering in a short cone. The 

 surface is finely striate axially, the strige cut on the last two 

 whorls by incised spiral lines (sometimes weak or nearly 

 effaced). Whorls 5% to 6, slightly convex, the last com- 

 pressed laterally. Aperture small, semioval, angular at both 

 ends. Outer lip obtuse, thickened within ; columellar lamella 

 small, situated near the base. Columellar lip reflexed and 

 adnate, the axis imperf orate or having a short, narrow crevice. 

 Being fossil, the shells are white and chalky. 



Length 14, diam. 7.1, aperture 6 mm. 



Length 14.5, diam. 7.3, aperture 6 mm. 



Length 13.8, diam. 6.3, aperture 5.8 mm. 



Oahu: Diamond Head, near Honolulu, in a Pleistocene or 

 Holocene deposit. Types no. 104687 A. N. S. P., collected by 

 C. Montague Cooke, Jr. 



Undoubtedly a member of the A. textilis and transversalis 

 group, but much less robust than the cylindric forms of the 

 recent fauna and with a smaller aperture. It is more cylin- 

 dric than A. transversalis, which occurs farther east and on 

 the main range. 



