iio Original Descriptions of Achatinella. 



strict' which extend to the very apex. Color reddish brown becom- 

 ing paler towards the summit ; with two yellow bands, a broad 

 one encircling the umbilical region, a narrow one at the periphery, 

 the latter margined above with a delicate white line, which is 

 continued on the spire just above the suture and becomes lost on the 

 last whorl ; also with a narrow white line revolving below the 

 suture to the very tip of the apex. Whorls 5, convex, not mar- 

 ginate ; suture distinctly impressed. Aperture a little oblique, 

 oval, white, distinctly exhibiting the dark coloring of the exterior; 

 peristome acute, slightly thickened within, the coloring of the out- 

 side appearing on the inner edge ; columella brown, terminating 

 in a well developed, flexuous fold. Length 14 1-2, diam. 9 mm. 



Animal when extended in motion longer than the shell. Mantle 

 light brown mottled with black, outer edge encircled with an in- 

 terrupted orange band. Foot above and below a very light brown, 

 superior portion with a slate tinge, posterior portion tapering and 

 sometimes with a yellowish tinge. Tentacles long, light slate. 

 Head above minutely granulated. 



This species was eollec~ted in the forest of the exterior slope 

 of the extinct Haleakala crater, at an altitude of 4000 feet above 

 sea level. Owing to its peculiar habit of living on the foliage near 

 the tops of trees, it has escaped previous observation. The species 

 has no known congeners. It is remarkable for the constancy of 

 its delicate color lines. Over two hundred examples before me 

 show only trifling divergence in this respect. — Bald. 



Hab. Makawao. — Bald. 



NIVEA GROUP. 

 178. Achatinella nivea Baldwin. 



./. nivea Bald. P. Acad. Phil., 1S95, p. 222, pi. x, fig. 19. 



Shell sinistral, subperforate, somewhat solid, acuminately ovate- 

 conic, apex acute ; surface highly polished, obliquely striated with 

 fine lines of growth, and under a lens showing very close and deli- 

 cate decussating spiral striae ; nuclear whorls faintly decussated. 

 Color white, encircled with a narrow, pale chestnut band on or a 

 little below the periphery. Whorls 7, slightly marginate above, 

 flatly convex, the last with a somewhat angular periphery and 

 flattened base. Suture slightly impressed. Aperture oblique, 

 roundly oval, white, the chestnut band of the exterior visible 

 within. Peristome white, acute, thickened within, expanded, basal 

 and columellar margins narrowly refiexed, extremities joined by a 

 very thin white callus. Columella white, terminating in a moder- 

 ately developed, flexuous plait. Length 24, diam. 14 mm. 



