Original Descriptions of Achatinella. 121 



collated; whorls 6 1-2, convex, margined with white; finely stri- 

 ated transversely, and microscopically decussated with faintly im- 

 pressed wrinkled spiral lines; the last regularly rounded, equal to 

 65-100 of the length; columellar fold well developed, white, oblique, 

 semioval; peristome thickened within, very slightly reflected; with 

 columellar margin dilated, adnate or slightly detached; parietal 

 margin wanting. 



Length 0.S5 in. (21 3-5 mill.), breadth 0.45 in: (11 2-5 mill.;. 



Length of aperture 0.38 in. (9 2-3 mill.). 



x\verage weight 5.70 grains. 



The dimensions of a large specimen are as follows: 

 Length 0.90 in. (23 mill.), breadth 0.47 in. (12 mill.). 

 Length of aperture 0.40 in. 

 Average weight 6.00 grains. 



Remarks. This shell differs from the A. splcndida Newc, in its 

 smaller size and pyramidal form, with spire less convex, body whorl 

 less ventricose, aperture smaller and less oblique, lip less expanded 

 and reflected. It also differs in being without perforation, and is 

 very rarely sinistral.— Gk. 



The A. perdix Reeve differs from this in its broader and more 

 ventricose form, its more convex spire, with whorls more swollen, 

 with aperture broader, and frequently subaugulated; the arrange- 

 ment of colors is also different. Looking only at the type of this 

 species, it would be placed in the same group with A. splcndida, 

 yet is so closely connected by intermediate varieties with A . perdix 

 that it has hitherto been considered a variety of that species. 



Yar. B. With black basal bands. A small specimen has the 

 following dimensions: length 0.80 in.; breadth 0.43 in.; length of 

 aperture 0.35 in.; weight 4.00 grains. 



Yar. C. Without band. I have a small specimen of the brown 

 variety of A. splcndida Newc. which closely resembles this. 



Yar. D. With apex chestnut brown, not tessellated; very rare. 



Yar. E. With irregular white spots. This variety passes into 

 A. perdix. 



Hab. Lahama— (S. T. Alex.)Gk. 



196. Achatinella ustulata Gulick. 



A. ustulata Gk. Aim. I. ye. New Vork, vi, 1S56, p. 211, pi. vii, fig. 57. 



Shell sinistral, perforate, ovate-conic, obliquely produced at the 

 base, solid, scarcely shining, striated, and microscopically distinctly 

 decussated, brown, with a whitish band encircling the base; apex 

 subacute, tessellated with white and brown; spire conical, some- 

 what curvilinear; suture simple, lightly impressed, marked with a 



