1896.] NATURAL SCIENCES OF PHILADELPHIA. 441 



edges, the upper and lower margins of the jaw bluntly denticulated 

 by the squarish ends of the ribs. Radula of the same type as in the 

 species previously mentioned. 



I have figured several specimens to show the variations of form 

 and sculpture. When mature the shell always has a pretty solidly 

 thickened peristome. The young are more translucent and show 

 projecting points of epidermis along the minute granular spiral lines, 

 as in B. wdfasciatus, and like that species show a distinct peripheral 

 paler band. 



Bulimulus (Naesiotus) Bauri Dall. Plate XV, fig. 12; Plate XVII, figs. 7, 15. 



Bulimuhis {Nicsiotus) Bauri\)2X\., Nautilus, VII, p. 54, September, 1893. 



Hibernating on the under side of leaves of plants at the south- 

 west end of Chatham Island, 1,600 feet above the sea. Dr. Baur. 



Jaw thin, light horn colored, arcuate, of equal height throughout, 

 with blunt ends ; anterior surface with about 12 broad, flat, crowded 

 ribs, their outer edges reinforced and their ends bluntly denticulat- 

 ing the upper and lower edges of the jaw. 



Radula long and narrow ; formula about 1 ; rachidian 



15+9-9+15 

 tooth and nine perfect laterals, differing little from those of the 

 other species already described ; marginals with the inner cusp 

 broad and bifid or at the extreme margin trifid, the outer cusp 

 broken up more or less irregularly into several denticles or groups 

 of denticles. 



Genitalia essentially as in B. mix. 



This is a very distinct little species, with a pale yellow-brown 

 body whorl darkening toward the tip of the spire, with conspicuous, 

 lighter transverse wrinkles on the upper whorls, and fine ribbing 

 on the nepionic shell which is of a livid purple, almost black. In 

 specimens which have survived hibernation, the aperture is usually 

 produced, contracted, and conspicuously thickened. Many speci- 

 mens have a narrow, pale line in front of the suture. There is no 

 spiral sculpture. 



Bulimulus (Naesiotus) amastroides Ancey. Plate XV, fig. 16. 



Bulinmlus {Nesiotm) amastroides Ancey, Bull. Soc. Mai. de France, IV, p. 

 293, 1887. 



Bulimuhis jacobi Stearns, Proc. U. S. Nat. Mus., XVI, pp. 381, 426, 1893, 

 not of Sby. 



Bulimulus calvus var. ? Stearns, op. cit., p. 427. 



Chatham Island, U. S. Fish Commission. 



This is the smooth form of which the plicate aspect is B. curtus of 

 .Reibisch and Anceyi of Dall. Jaw membranaceous, horn colored, 

 29 



