200 



AMASTRA, OAHU. 



Shells from Kawailoa are similar but rather smaller and 

 shorter. There is an inner, somewhat glossy cuticle of very 

 pale buff, covered with a very thin dull outer layer of a 

 slightly darker shade, worn off in front of the aperture. The 

 specimens from Kahana are similar. The original figure is 

 copied. 



39. A. DECORTICATA Gulick. PI. 33, figs. 4, 5, 6, 7. 



"Shell ovate-conic, dextral, lightly striated with lines of 

 growth; chestnut, blackish towards the lip. Whorls 6 to 6y 2 , 

 a little convex, the first 3 polished ; suture simple, pale. Aper- 

 ture weak dirty-blue inside. Peristome thin, blackish within, 

 scarcely thickened; columellar fold thin. Length 16, diam. 

 8.5mm." (Gulick). 



Oahu, western part of the main range: Kawailoa, type 

 locality; Helemano, Opaiula, Waimea, Waialei, Kahuku and 

 Kahana (Gulick). Under dead leaves in the forest. 



Amastra decorticata Gk. in GULICK and SMITH, P. Z. S., 

 1873, p. 84, pi. 10, f. ll.Achatinella cl, PFR., Monogr., viii, 

 240. Achatinella d., THWING, Orig. Descr. Achat., p. 149.- 

 Achatinella decortica BALDWIN, Catalogue, 1893, p. 8. Latni- 

 nella decorticata Gul., W. G. BINNEY, Ann. N. Y. Acad. Sci., 

 iii, 1884, p. 98, pi. vi, f. D (teeth). 



'It is allied to A. elliptica Gk., the metropolis of which lies 

 to the northwest of this, and to A. in flat a Pfr., which is found 

 in the valleys to the east. It is always dextral" (Gulick). 



A series of several hundred shells from all the above local- 

 ities except Helemano shows this to be quite a constant species. 

 It never has the conspicuously patched clothing of A. in flat a 

 and elliptica, though under a lens some small dull streaks 

 may be seen on the otherwise rather glossy surface, which 

 elsewhere shows no epidermis in the typical form. The color 

 is reddish-chestnut of varying intensity, frequently shading 

 into yellowish on the upper part of the last whorl, and always 

 much darker behind the lip. The spire is frequently darker, 

 purplish-brown. The suture is usually marked with a yel- 

 lowish line, but this is often wanting. There are 2V 2 em- 

 bryonic whorls, the last one very lightly, minutely and un- 



