214 AMASTRA, OAHU. 



Arts and Sciences, i, 1827, p. 49, pi. 4, f. 5. A. inornata 

 MIGHELS, Proc. Best. Soc. N. H., ii, 1845, p. 21. 



"Animal short, only half as long as the shell, of a dark 

 slate-color on the sides ; superior portion and tentacles black ; 

 under surface of foot light gray; mantle dark brown" (New- 

 comb). 



Nuuanu valley may be taken as the type locality of this 

 very distinct species. The typical form, as figured by Ferus- 

 sac, is chestnut-brown. The embryonic shell is often some- 

 what darker, purplish, but it may be whitish- corneous or 

 flesh-colored. The apex is rather blunt and rounded, second 

 embryonic whorl very finely striated vertically, the striae in- 

 terrupted by some weak spirals. The adult stage has fine 

 striae over low growth-wrinkles. The subsutural region is 

 generally paler-colored. Aperture blue-white or with a faint 

 pink tint within. Outer lip acute; columellar plica not very 

 strong, and often there is a low, oblique fold above it. Axis 

 generally perforate. Length 20, diam. 8.7, aperture 7.5 mm. , 

 7 whorls; fig. 2 (Nuuanu valley, C. M. Cooke). Other color- 

 forms from Nuuanu valley are as follows : 



2. Fig. 1. Chocolate-brown, with or without a yellow sub- 

 sutural line. Length 23, diam. 9, aperture 8 mm. ; 8 whorls. 



3. Fig. 3. Yellow, shading into chestnut towards the end 

 of the last whorl, apex generally dark ; a white subsutural 

 line sometimes present. 



4. Pale, corneous-buff, the apex generally pale, last whorl 

 showing traces of a thin, pale brownish cuticle (fig. 4, Matiti) . 



Two small specimens from Waialae resemble forms 1 and 3. 

 A series from Palolo contains forms 1 and 4. In Moanalua 

 Cooke found form 2 and an intermediate between 3 and 4. 

 In Halawa we have form 3 and intermediate between 3 and 4. 

 In Matiti ( Gulick, = M-akikd ? ) forms 2, 3, 4 (fig. 4). 



The synonymous A. oahuensis had the typical coloring of 

 turrit ella. A. inornata Mighels had forms 1 and 4, and may 

 have been from Palolo. 



Dr. C. Montague Cooke informs us that A. turritella is found 

 in grass, and on 'both aerial roots and leaves of the leie (Frey- 

 cinetia)* When on these roots the shell is covered with a 



