82 LEPTACHATINA, S.-G. THAANUMIA. 



ever, in being smaller, the surface is more distinctly sculp- 

 tured, the aperture is broader in proportion to its length and 

 there is a distinct, though minute, perforation. 



106. L. CHRYSALLIS (Pfeiffer). PL 4, figs. 77, 78. 



''Shell oblong turrited, somewhat solid, slightly striate, 

 arcuately plicate at the sutural line, pale yellowish; spire 

 subcylindrical, apex conic, obtuse; whorls 10, nearly flat, the 

 last nearly equal to % of the length, rotundate at the base; 

 columella callous, abruptly truncate at the base ; aperture ver- 

 tical, sinuately semioval; lip erect, with the dextral margin 

 arcuate, thickened within. Length 9.0, diam. 3.5 mm." 

 (Pfr.) 



Oahu: Waialua (Baldwin, Lyman), Waianae Mts. and 

 Wahiawa (Cooke). 



Achatina chrysallis PFEIFFER, P. Z. S. London, 1855, p. 99 ; 

 Mon. Hel. Viv., iv, p. 617; vi, p. 238. Achatina (Electro) 

 chrysallis PFR., Malak. Blatter, 1856, p. 169. Lepta- 

 chatina chrysallis PEASE, P. Z. S., 1860, p. 650. Leptachatina 

 columna ANCEY, Le Naturaliste, 1889, p. 266. SYKES, Proc. 

 Malac. Soc. London, iii, pi. 13, fig. 18. Leptachatina chry- 

 sallis SYKES, Fauna Haw., ii, 1900, p. 358. 



This species is never abundant in any one locality, but 

 seems to be distributed over a rather large area. A single 

 specimen from Nuuanu is referable to this species, though 

 doubtfully. I have examined both Ancey's and Pfeiffer 's 

 types and there is no doubt that both belong to the same 

 species. 



Unfortunately I have no young specimens of this species, 

 the basal palatal lamella does not appear in adult specimens. 



Subgenus THAANUMIA Ancey, 1899. 



Thaanumia ANCEY, Proceedings of the Malacological So- 

 ciety of London, iii, July, 1899, p. 269, monotype T. ompha- 

 lodes. 



The shells are openly umbilicate or perforate, sometimes 

 imperforate, hardly glossy, of a silky texture, thin or some- 

 what solid, costulate to .costate, with the embryonic whorls 



