AMASTRA. 29 



are also strong, yellowish and roughened. It is evidently a 

 very old shell which has added to the peristome in the senile 

 stage, after normal growth had been completed. This speci- 

 men supplied part of Pease's description the phrases "more 

 rarely rounded-angulate at the base" and "Peristome 

 rugose, calloused, the margins joined by a thick callus" 

 applying to it. 



A. MONTAGUI Pilsbry. PL 5, fig. 13. 



The shell is sinistral, imperforate, oblong-ovate, rather thin, 

 chestnut-colored, with a denuded ecru-olive patch in front of 

 the aperture and an ill-defined yellowish band below the 

 suture. The very thin cuticle is somewhat dull. Outlines of 

 the spire are somewhat convex, the summit rather obtuse. 

 The whorls are most convex close below the suture. Surface 

 finely sculptured with unequal growth-ripples; embryonic 

 whorls very minutely, indistinctly striate, convex. The aper- 

 ture is oblique, slate-violet within; outer lip acute, black- 

 edged, with a slightly thickened whitish submargin within. 

 Colurnellar lamella thin, rather steeply ascending, subtriaugu- 

 lar. Length 13, diam. 7.75, aperture 6 mm.; 5~y 2 whorls. 



Oahu : Summit of the Main Range, between Waiahole and 

 Waiawa, D. Thaanum. Cotypes no. 108172 A. N. S. P. and 

 6842 Thaanum coll. 



Amastra montagui PILS., Nautilus xxvii, August, 1913, p. 39. 



This species, which was named in honor of Doctor C. 

 Montague Cooke, is related to A. thaanumi, which was found 

 in Kaaawa, on a lateral spur of the Main Range, some miles 

 north of the habitat of A. montagui. The main difference 

 between the species is that A. montagui is much more slender. 



This is the second sinistral Amastra from Oahu. All other 

 sinistral species of the genus belong to the subgenus Heter- 

 amastra, and live on the islands Molokai, Maui, Lanai and 

 Hawaii. 



A. RETICULATA Pfr. Vol. XXI, p. 179. 



Typical specimens were taken by Mr. Thaanum in Haleauau, 

 and by Pilsbry at the foot of a small intermediate ridge in 

 Popouwela. In both lots, there were also some subcjdindric 



