224 LYROPUPA. 



last two whorls often weak or sometimes interrupted in the 

 middle. The last half- whorl has one long and two short spiral 

 furrows. The ribs extend over the base. The aperture has 

 the usual angular and parietal lamella?. The columellar 

 lamella is readily visible in a front view. The upper-palatal 

 is conspicuous, as usual. Below it, and somewhat immersed, 

 the lower-palatal is seen. The basal fold is represented by a 

 low tubercle below the inner end of the lower-palatal fold. 



Length 2.3, diam. above aperture 1.1 mm. ; 5 whorls. 



Hawaii (Pease, No. 45327 M.C.Z.) ; Kona crater (Thwing). 

 Waiaha (A. Gouveia). Also Kahoolawe, Lanai and Molokai. 



Vertigo costata Pease, Proc. Zool. Soc. London, 1871, p. 

 461; reproduced in this work, vol. xxv, p. 272. — Lyropupa 

 kahoolavensis Pilsbry and Cooke, Man. Conch., xxv, p. 256. 



By external characters this species is likely to be mistaken 

 for L. ovatula kona, but the palatal structure is quite distinct. 



Pease's description was altogether insufficient for the recog- 

 nition of the species, and in fact is inaccurate ; but as his 

 types have been found it seems best to recognize this widely- 

 spread snail under his name. 



Lyropupa ovatula kona Pils. and Cooke. PL 28, figs. 9, 10, 

 15, 16, 17. 



Vol. XXV, p. 266, exclusive of pi. 26, fig. 5, and the locality 

 Moomomi, Molokai. 



New figures are given of the type from Huehue (figs. 9, 10, 

 15) and specimens from Kapulehu (figs. 16, 17). While this 

 form is closely related to L. ovatula of Oahu, it differs by 

 having a distinctly ribbed base, three distinct impressions 

 over the palatal folds, and the basal fold is well developed. 

 In some cases the lower-palatal and basal folds are more or 

 less contiguous and united, as in fig. 15, a Huehue specimen, 

 but usually they are quite separate, as in figs. 16, 17, Kapu- 

 lehu. The diagrams of palatal structure, figs. 15, 16, 17, were 

 inadvertently reversed by the artist. 



The Kapulehu form has a deeper constriction of the last 

 whorl than the type form from Huehue, and the ribs are 

 strongly developed and even. 



