'234 PKOCEEDINGS OF THE ACADEMY OF [1895. 



in the rock, as there is no satisfactory way to account for their 

 transportation from any distance. If so, the conditions of climate 

 when the shells flourished in that locality, must have been quite 

 different from those of the present time. 

 Amastra cyclostoma, n. sp. PI. XT, fig. 53. 



Shell dextral, narrowly but deeply perforated, the perforation 

 penetrating to the apex, somewhat solid, oblately globular with a 

 short conical spire, apex acute ; surface lustreless, sculptured with 

 close, obliquely descending, flexuous growth lines, which become con- 

 centric around the umbilicus ; the embryonic whorls smooth or with 

 delicate, radiating suleations. Color brown, darker on the spire. 

 Whorls 6, the upper ones rather flat, rapidly increasing; the last 

 one large, forming the greater part of the shell, strongly angled at 

 the periphery, the angle becoming almost obsolete towards the aper- 

 ture, deflexed in front a trifle below the carina, surface above the 

 angle flat, slightly convex towards the aperture, and rounded below 

 the, angle ; suture well impressed. Aperture very oblique, sinuately 

 circular, a small segment cut off by the penultimate whorl, livid- 

 white within, exhibiting the exterior coloring through its substance: 

 peristome rather obtuse, slightly thickened within, unreflected, ex- 

 tremities slightly converging and united by a very thin callosity; 

 columella livid-white, broad and flat, terminating in a slight, flexu- ' 

 ous plait. 



Altitude, 15; diam. 18 mm. 



Habitat, Makaweli, Island of Kauai. 



Animal when extended in motion. 95 inch in length; posterior 

 portion of foot tapering and very short, front portion long; head 

 elongated, ocular and labial tentacles widely separated. Mantle 

 dingy-white with streaks of black. Foot very light brown, superior 

 portion and sides thickly studded with regular, dark brown granula- 

 tions. Tentacles long, dark brown. 



This species belongs to the same group as Amastra sphavrica Pse. 

 and Amastra heliciformis Anc. , but may be readily distinguished from 

 both by its much larger size and more inflated body whorl. 



Amastra Knudsenii, n. sp. PI. XI, figs. 13, 14. 



Shell dextral, imperforate, solid, elongately ovate, spire conical, 

 apex subacute ; surface lustreless, coarsely and irregularly wrinkled 

 by growth striae ; embryonic whorls very finely radiately sulcated. 



