Three New Species of A mast ra from Oahu. 19 



(Conch.' Icon., Achatinella, No. 31). It is much larger than any 

 specimens of Reeve's species and more cylindrical in outline. 

 The spiral thread on the third and fourth whorls is peculiar, as 

 are the rather pronounced striae on the third whorl. 



A second specimen, in the Bishop Museum collection, is 

 younger, with 6-|- whorls. It is slightly more convex in outlines 

 and measures : length 17.2, diam. 9.7 mm. 



Amastra davisiana, n. sp. 



Fig. 1. 



The shell is perforate, dextral, subconic, with slightly convex 

 outlines, obtusely and faintly angular at the periphery, with a 

 somewhat flattened base, rather solid, nearly smooth, distinctly 

 and almost regularly striate just below the sutures, slightly glossy, 

 dark reddish brown, with an indistinct broad dark band just above 

 the periphery and continued on the spire just above the sutures. 

 Spire almost conic, apex very obtuse. Suture minutely crenulate, 

 scarcely impressed, yellowish along its edge. Whole 6^, the 

 embryonic rather large (for the genus), the rest increasing slowly 

 and very regularly, almost flat, the last descending slightly near 

 the aperture. Aperture small, subquadrate, oblique, bluish with- 

 in. Inner margin of the columella slightly diagonal, outer margin 

 nearly straight; columellar fold nearly basal, strong, thick, 

 slightly oblique. Outer margin of lip thin, slightly thickened 

 within, nearly straight above, curved below, forming something 

 of an angle with the base of the columella ; columellar margin 

 thin, reflexed above the umbilicus. Umbilicus small, semicircular. 

 Length 16.5, diam. 9.2, length of ap. (diagonal) 7.0 mm. 



Oahu : About a mile from the summit of Konahuanui (Davis); 

 summit of Konahuanui (Spalding). 



Type No. 16,454, Bishop Museum Coll. 



I know of no species to which this is at all related. It is en- 

 tirely distinct from any of the other species of Amastra. The 

 blunt apex and very regularly coiled and almost flat whorls are 

 very peculiar. The single type specimen was originally collected 



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