LEPTACHATINA, GROUP O. 71 



slightly larger than those described by Pease. An average 

 specimen measuring, length 11.3, diam. 5.3, length of aperture 

 4.6 mm. Those from Halemanu are smaller. A well de- 

 veloped specimen measuring, length 9.2, diam. 4.5, length of 

 aperture 4.1 mm. 



This species appears to be distantly related to L. fusca 

 Newc., from Oahu. The embryonic whorls are slightly com- 

 pressed and very slightly shouldered, though less so than in 

 the latter species. In L. balteata the embryonic whorls are 

 not strongly striate, but are almost smooth. 



93. L. COSTULOSA Pease. PI. 7, fig. 42 ; pi. 12, fig. 6. 



"The shell is elongate, turrited, thin, imperf orate, dextral, 

 longitudinally closely costulate; whorls 8, somewhat flat, 

 scarcely crenulate at the suture, the last almost equal to % 

 of the length; aperture small, broadly elliptical, subvertical, 

 angulate at the base of the columella; columellar fold small, 

 oblique ; columella erect, callous, white ; lip scarcely thickened ; 

 yellow, often colored with purple at the suture. Length 14.0, 

 diam. 5.0 mm." (Pse.) 



Kauai (Pease) : Waimea and Kealia (Baldwin). 



Leptachatina costulosa PEASE, P. Z. S., 1869, p. 651 (nom. 

 sol.} ; Journ. de Conchyl., 1870, p. 90. CROSSE, Journ. de 

 Conchyl., 1876, pi. 3, fig. 4. Achatinella (Leptachatina) 

 costulosa PPR., Mon. Hel. Viv., viii, p. 248. 



"L. striatula Gould is the closest related species to this" 

 (Pse.). I have seen but four specimens which might possibly 

 be referred to this species. These were in Mr. Thaanum's 

 collection and were collected by Mr. Baldwin. The species 

 appears to be more closely allied to L. tenebrosa Pse., than to 

 L. striatula. From the former it differs in being larger, with 

 a broader spire, much lighter in color and with a slightly 

 more diagonal aperture. It may ultimately prove to be a 

 variety of this species. The original figure is copied on pi. 7. 



94. L. EXTENSA Pease. PI. 8, fig. 67. 



"The shell is elongate, slender, imperf orate, dextral, some- 

 what solid, glossy, longitudinally closely impressed striate; 



