246 ' Third Supplement to Dana’s Mineralogy. 
Art XXIL—Third Supplement to Dana’s Mineralogy; by the 
Author.* — 
Since the last Supplement was issued, but few new species 
have been proposed and several of these are of doubtful stand- 
edges, although so delicate as to require a glass to distinguish 
them. Having received specimens from Professor Scacchi, the 
American mineralogy, there has been the publication of 
some geological reports containing information on useful mine 
rals and ores, and a few articles in the Journals. The only new _ 
minerals have been announced ina mining report, and in this 
volume (p. 96), by Prof. C. U. Shepard. 
It is a 
n 
brought out, ppeually in this country, without sufficient inves- 
tigation and ful ipti i 
gions of error; and often much and long labor is required be- 
fore the science recovers from these backward steps. 
1, List of New Works, 
Dr. Cart Friepricn Naumann (Liepzig): Elemente der theoretischen Krystallo- 
graphie, 384 pp., 8vo, with 86 wood-cuts. Liepzig—This volume is oun & 
supplement to the former one (Anfangsgrunde der. Krystallographie) published in 
1854. In that, the elements of the science are explained and the besa for caleu- 
* For Supplements I and II, see this Journal, xix, 353 (May, 1855), and xxi, 198 
: e Mineralogy. 
(March, 1856). The paging inserted beyond, refers to the 
. 
. 
