22 



New Species of Amastra. 



A. montivaga, n. sp. 



PI. C. Fig. 5. 



The shell is perforate or imperforate, dextral, thin, nearly 

 smooth, faintly striate with growth -wrinkles, just below the sutures 

 there is a shallow sulcus which is transversely interrupted by 

 numerous strong striae which are slightly bent backwards, color 

 chesnut with a 5'ellowish zone around the columella. Embryonic 

 whorls convex, faintly and irregularly striate with growth-wrinkles. 

 The following whorls slightly convex, with a distinct shoulder 

 just above the sutures. The last whorl indistinctly angulate just 

 above the periphery. Aperture slightly diagonal, its outer mar- 

 gin slightly flattened above, curved below, edged with black and 

 furnished with a very thin lip-rib, and forming with the base of 

 the columella a broad sinus. Columella short, narrow, its outer 

 margin straight above, angled just outside the columellar fold. 

 Columellar fold basal in position, not strong, thin, terminating 

 somewhat gradually close to the outer margin of the columella. 

 Umbilicus (when present) minute, cleft-like. 



Length 12.4, diam. 7.3, apert. 5.7 mm.; 5^ whls. (Holotype) 

 13.2, " 7.3, " 6.0 " 6 



Oahu : Top of Maunakope, the peak as the head of the west- 

 ern Kalihi ridge (A. Gouveia). 



Holotype and cotype No. 41,988, paratypes. No. 41,098. 

 Bishop Museum, also in Gouveia collection. 



A. montivaga is undoubtedly a dirivative of A. textilis. It 

 differs from the latter species by its smaller size, thinner shell, 

 more convex whorls (which are shouldered below), deeper sutures, 

 etc. A specimen of A. textilis from the same locality measures 

 length 16.0, diam. 8.2, apert. has ^]i shorls. The penultimate 

 whorl of A. montivaga is slightly shouldered just above its suture 

 but the rest of the whorls do not show this character. In some of 

 the specimens of A. montivaga the yellowish zone occupies the 

 whorl of the shell below the periphery. 



A. paulula, n. sp. 



PI. B. Fig. 6. 



The shell is perforate, dextral, ovate, in its fossil state very 



light brown, rather thin. Outlines of the spire convex, with an 



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