LYROPUPA. 243 



Length 2.75, diam. 1.67, aperture 1 mm. (type). 



Length 2.5 mm. 



East Maui : Auwahi, type loc. (Thaanum) ; Ukulele (Forbes) . 

 Type 11043 Bishop Museum ; paratypes 36896 Bishop Museum, 

 119452 A. N. S. P. and 7597 Thaanum collection. 



This species is related to L. rhabdota and its subspecies. It 

 differs, however, in its larger size, more cylindric outline and 

 the depressed, rounded summit. The same character separates 

 it from L. prisca, which appears to be the most closely allied 

 species. L. thaawumi is also related to L. truncata, but is 

 easily separated by its less flattened apex, thicker shell and 

 especially by the finer and closer spiral striae on the last whorl. 



5. LYROPUPA PRISCA (Ancey). PI. 20, figs. 9, 10, 11. 



The shell is sinistral, rimate-perforate, subcylindrical, in its 

 fossil state pinkish cinnamon with a narrow nearly white band 

 above the periphery on the last two whorls, thick, opaque,, 

 strongly costate, with 15 to 17 slightly oblique ribs on the last 

 whorl; the interstices very minutely, closely, spirally striate 

 (but in its fossil state these striae are usually absent). Spire 

 subcylindrical, tapering gradually above to a rather obtuse- 

 apex; individual whorls convex, separated by a deep suture.. 

 Whorls 5% to 5%, the embryonic 1% whorls (under a strong 

 lens) nearly smooth, only traces of minute close, spiral striae 

 remaining. The last whorl ascends slightly towards the aper- 

 ture, and, tapers very gradually to the base; it has two dis- 

 tinct nearly parallel shallow sulci which unite further in back 

 into a broad shallow furrow. Aperture perpendicular, roughly 

 triangular with broadly rounded base, its margins continuous. 

 Angular lamella long and strong, emerging to the margin. 

 Parietal lamella thinner than in most of the species and de- 

 cidedly slanting outwards. Columellar lamella strong, deeply 

 seated, obliquely entering, high in front, low in back, running 

 into the columella above. Upper palatal fold long, extending 

 nearly to the margin, high within, very low where opposite the 

 angular. Lower palatal fold shorter and broader, deeply 

 seated, nearly parallel to the upper, and penetrating inward 

 beyond it, either simple or divided by a median depression 



