122 Original Descriptions of Achatinella. 



narrow white line; whorls 6 1-2, moderately convex; the last large, 

 equal to 72-100 of the length; columellar fold strong, white, ob- 

 lique; aperture very oblique, sinuously oval; peristome thickened 

 within, reflected anteriorly; with columellar margin dilated, white, 

 unattached; parietal margin wanting. 



Length 1.00 in. (25 2-5 mill.), breadth 0.57 in. (14 1-2 mill.). 



Length of aperture 0.52 in. (13 1-5 mill.). 



Weight 10.00 grains. 



Station. On the Mamaki {Pipturus albidus) . 



Remarks. This species is more ventricose than A. pcrdix 

 Rve., and differs in having the whorls more convex, the suture 

 simple, the aperture more oblique, and the sculpturing more dis- 

 tinct. I have received but two specimens, for which I am indebted 

 to the brothers James and Samuel Alexander. — Gk. 



Hab. Beautiful Valley. — (S. T. Alex.)Gk. 



197. Achatinella undosa Gulick. 



A. undosa Gk. Ann. Lye. New York, vi, 1S56, p. 205, pi. vii, fig. 33. 



Shell dextral, deeply, narrowly umbilicate or perforate, acumi- 

 nately ovate-conic, solid, shining, finely striated, and microscopi- 

 cally very faintly decussated, lead-gray, streaked and waved with 

 black, brown and white; apex subacute, tessellated with white 

 and chestnut; spire conic; whorl 6 1-2, somewhat swollen above, 

 slightly margined; the last equal to 0.65 of the length; columella 

 white, moderately plicate; aperture somewhat oblique, sinuously 

 oval; peristome thickened within, slightly reflected anteriorly; with 

 columellar margin dilated, unattached; parietal margin wanting. 



Length 0.93 in. (23 mill.), breadth 0.47 in. (12 mill.). 



Length of aperture 0.42 in. (10 2-3 mill.). 



Average weight 5.50 grains. 



The dimensions of a large specimen are as follows: 



Length 1.00 in. (25 1-5 mill.), breadth 0.50 in. (12 2-3 mill.). 



Weight 8.00 grains. 



Var. B. Much smaller. 



Length 0.74 in. (19 mill.), breadth 0.42 in. (10 2-3 mill.). 



Length of aperture 0.33 in. (8 2-5 mill.). 



Weight 4.00 grains. 



Var. C. With interrupted dingy white bands encircling the 

 base; quite rare. 



Var. D. Ventricosely ovate; spire short; whorls 6, swollen, 

 the last flattened in the middle; rare. 



