TUE NAUTILUS. 107 



ceived a couple of specimens of this form (max. diam. barely over 12 

 mm.), collected by Mr. C. S. Onderdonk, at Alpine, Chaffee county, 

 Colorado, at between 10,000 and 12,000 ft. This is a long way from 

 the original locality, but I sent one to Dr. Ball, who certified that it 

 is the genuine concentrata. There are two dark bands, both narrovr 

 but strongly developed. This var. concentrata is extremely close to 

 my var. minor (max. diam. 14 mm.), described in Journ. of Con- 

 chology, 1890, p, 175. The latter, however, is not alpine. 



No doubt the Colorado concentrata have evolved independently 

 from the New Mexico and Arizona ones, and, therefore, might per- 

 haps be considered entitled to a different name. T. D. A. COCK- 

 ERELL. 



ERRATUM. 



NAUTILUS, p. 96, line 8 from top: For coniformis read corvi- 

 formis T. D. A. COCKERELL. 



PUBLICATIONS RECEIVED. 



THE MOLLUSCA OF THE MT. MITCHELL REGION, NORTH CARO- 

 LINA By Bryant Walker and H. A. Pilsbry. Proc. Acad. Nat. 



Sci., Phila., 1902, pp. 413-442, Pis. xxiv, xxv. In vol. xiv, p. 45, 

 we noticed Professor Pilsbry's account of the Mollusca of the Great 

 Smoky Mountains. The present paper sets forth the results of the 

 exploration of the French Broad river region by Messrs. Ferriss and 

 Walker "and two ladies" in 1901. The Roan Mountain fauna 

 being pretty well known from the investigations of Wetherby, Walker 

 and others, it now becomes possible to determine with some degree 

 of accuracy the range of the different species in this part of North 

 Carolina and adjacent Tennessee. It had previously been made 

 clear that the Roan Mountains and Great Smoky regions, though 

 only about seventy-five miles apart, possessed molluscan faunae which 

 were by no means identical ; the expedition of 1901 sought to deter- 

 mine whether the valley of the French Broad river might be the 

 dividing line between the Roan and Great Smoky faunae, and whether 

 Mt. Mitchell, with an altitude of 6,711 ft,, might not produce some- 

 thing peculiar to itself. With the results of the expedition before 

 them, the authors conclude that the French Broad river is not the 

 dividing line between the two faunae just mentioned, and, in fact, 



