LYROPUPA. 263 



Length 2.5, diam. 1.18, apert. 0.75 mm.; Niihau: Kiekie 



(Stokes). 



17. LYROPUPA MICRA C. & P., n. sp. PI. 23, fig. 7; pi. 25, 

 figs. 5, 6, 7. 



The shell is smaller than L. perlonga, the whorls nearly fiat ; 

 ochraceous-tawny, with sculpture of many low riblets, which 

 are somewhat irregular and unevenly spaced. The last half- 

 whorl has the usual three impressions well developed, and be- 

 low the middle there is a vertical ridge or hump, running to 

 the base, about a third of a whorl behind the outer lip. The 

 sinulus is small and rounded. The parietal lamella is not 

 very long, but penetrates beyond the strong columellar lamella, 

 which is straight and vertical. The upper palatal lamella 

 penetrates to the dorsal side. Lower palatal is deeply im- 

 mersed, short but large. The basal fold is narrow and longer, 

 but also deeply placed. There is a vertical barrier below the 

 end of the upper palatal, composed of two strong tubercles 

 separated by a rather narrow sinus. 



Length 1.9, diam. 1.1 mm.; 5 whorls (Kaelepulu, type). 



Length 1.9, diam. 1.05, aperture 0.65 mm.; 5 whorls 

 (Lualualei). 



Length 1.8, diam. 0.95, aperture 0.65 mm.; 5 whorls 

 (Rocky Hill). 



Oahu: Kaelepulu, Kailua, on a lime-rock bench about % 

 mile from the north shore (Pilsbry, type loc.). Eocky Hill, 

 Manoa valley (Cooke; fig. 7) ; and in the Waianae region at 

 Lualualei (Cooke) and Kawaihapai (Cooke and Pilsbry). Liv- 

 ing at Lualualei, elsewhere fossil. A subspecies in Molokai. 



L. micra is more slender than L. thaumasia. The dorsal 

 hump, while variable in prominence, appears to be constant 

 in the great number seen. Both on Oahu and 011 the dry 

 western part of Molokai it occurs with larger species of the 

 perlonga group. The living specimens from Lualualei are 

 cinnamon-colored. 



The specimens from Kaelepulu, Kailua (pi. 25, figs. 5, 6, 7), 

 have the sculpture weaker than most of those from Eocky 

 Hill though there are often prominent, thin laminae near the 



