170 AMASTRA, OAHU. 



Amastru spah/iinji COOKE, Oecas. Pap. B. P. Bishop Mu- 

 seum, iii, p. 18 [214], f. 2 (July 24, 1908). 



Figured from specimens 17738 and 17612, Bishop Mus. 

 Its nearest congener is probably A. textilis Fer., from' which 

 it differs by the larger size, more cylindric form, and espec- 

 ially by the spiral threads above the suture, on the third and 

 fourth whorls, a feature peculiar to this species. These 

 spirals are best shown in the enlarged view of the neanic 

 stage, pi. 38, fig. 13. Named in honor of Mr. Irwin Spalding, 

 of Honolulu. 



16. A. PELLUCIDA Baldwin. PI. 30, fig. 13. 



"Shell dextral, imperf orate, very fragile, thin, translucent, 

 globosely conic, apex rather acute; surface lusterless, sculp- 

 tured with fine incremental lines, apical whorls smooth. Color 

 light-brown, apex darker; destitute of epidermis. Whorls 

 5y 2 , somewhat convex; suture moderately impressed. Aper- 

 ture oval, a trifle oblique, livid-white within; peristome simple, 

 thin; columella white, flexuous, abruptly terminating in a 

 thin lamellar plait. Length 12y 2 , diam. 8 mm. 



"Animal of a uniform brown color-, the 'head above and 

 tentacles of a darker shade. The action of the heart is plainly 

 visible through the thin texture of the shell. When first col- 

 lected the pulsations were about fifty per minute, growing 

 slower and fainter from day to day until the animal died" 

 (Baldwin) . 



Oahu : Waianae Valley. Co-types no. 65721 A. N. S. P. 

 Amastra pellucida BALDWIN, Proc. A. N. S. Phila., 1895, p. 

 231, pi. 11, f. 45, 46 (not f. 41. 42). 



"This species is well characterized by its thin pellucid tex- 

 ture, globose form, abbreviated spire, and light brown color" 

 (Baldwin] . 



The type specimen which served for Mr. Baldwin's meas- 

 urements and fig. 45 of his plate is drawn in fig. 13. It is an 

 adult shell, white under a thin, very pale straw-colored cuticle, 

 which is deciduous in a band below the suture, the first 3 

 whorls being rather light brown and smooth. Though thin, 

 it is not fragile, but moderately strong. The aperture is white 



