186 AMASTRA, OAHU. 



bryonic whorls radiately sulcated. Color dark chestnut-brown 

 with light brown zigzag or undulating lines and markings. 

 Whorls 6%, slightly convex; suture moderately impressed. 

 Aperture oval, a trifle oblique, livid white within, exhibiting 

 the brown color of the exterior ; peristome acute, very lightly 

 thickened within ; columella white, flexuous, abruptly termin- 

 ating in a thin, slightly arched lamellar plait. Length 20%, 

 diam. 10% nun." (Baldwin). 



Oahu: Ewa (Baldwin) ; Moanalua, Aeia and Waimano (C. 

 M. Cooke) . 



Amastra badia BALDW., Proc. A. N. S. Phila., 1895, p. 230, 

 pi. 11, f . 40. 



In color, pattern and sculpture of the later whorls this 

 form resembles A. undata. Whether there are spiral decus- 

 sating lines on the last whorl of the type specimen was not 

 stated by Baldwin, but they are present in one specimen ex- 

 amined from Moanalua, wanting in another. In those from 

 Waimano the spirals are either very faint, hardly noticeable, 

 or wanting. A. badia differs from undata by its embryonic 

 sculpture and the less obese, more ovate shape. 



The columellar lamella penetrates two whorls. The axis is 

 imperforate in the adult and later neanic stages, but in the 

 half -grown shell there is a rather widely open umbilicus, 

 width 'about 1 mm. 



The embryonic whorls (pi. 29, fig. 19) are much more 

 strongly sculptured than in A. undata. After the smooth 

 initial half -whorl, coarse vertical ribs appear, changing to an 

 irregular coarse malleation on the last half of the second 

 Whorl. Then short, rather coarse protractive ribs appear 

 below the suture, while above the lower suture there is another 

 system of smaller, retractive folds, the two systems interfer- 

 ing about the middle of the whorl. The third whorl has fine 

 growth-lines only, and the color-pattern appears as a few 

 white spots and irregular stripes. The ground-color of adults 

 is dark red, upon which there are yellow streaks or spots. In 

 some shells from Aeia the last whorl has a yellow suffusion, 

 faintly mottled with dark. The shell is quite thin. 



Fig. 15 is a copy of Baldwin's type figure; figs. 18, 19 are 

 immature shells from Waimano. Type in Baldwin coll. 



