148 The American Naturalist. [February, 
MINERALOGY. 
Minerals from the Chromite Deposits of Lower Silicia.— 
Traube? describes serpentine, albite, chromite, kämmererite and rutile 
from the chrome deposits of Tampadel in the Zobtengebirge in lower 
Silicia. The kämmererite is found to some extent in crystals a centi- 
meter across of greenish, reddish, or violet color, and either in hex- 
agonal plates or in combinations of hexagonal pyramid and base. In 
transmitted light thin cleavage plates show a division of the field into 
a central uniaxial portion, and six marginal biaxial areas. The mar- 
ginal areas have an optical angle of 20°-30° with the plane of the 
axes parallel to the marginal edge. In the same paper cerussite, Igle- 
siasite, Tarnowitzite, hemimorphite, pyrrhosiderite and sulphur are 
described from the upper Silician ore region. The cerussite is inter- 
esting because of the wealth of the crystals in forms. A crystal from 
the Friedrichsgrube showed nine forms including the new form 
a=4P (441). Another crystal exhibited eighteen forms including 
the two new forms f =% P7 (170) and g = 7P7 (171). Iglesiasite, the 
zine-bearing cerussite, which has been known from but the one locality 
of Monti Poni near Iglesias in Sardinia, is found on smithsonite in good 
crystals at Radzionkau. The forms x (012), i (021), y (102), e (101), 
i (210), m (110), r (130), p. (111), and o (112), were observed and 
measured, the form i =æ P2 (210) being new to cerussite. Chemica] 
analysis showed the mineral to contain 5.47 per cent. ZnCO,, while 
that from Iglesias contains 7.02 per cent. Tarnowitzite, the isomor- 
phous mixture of calcium and lead carbonates is studied in the origi- 
nal locality of Tarnowitz. The mineral is sometimes clear and color- 
less, but is also green, reddish-brown, or yellowish. Lead carbonate is 
present up to 9 per cent in some specimens. All of the four analyses 
made from specimens differently colored, showed the presence of a 
small per cent (up to 0.35) of Sr O. A number of brachydomes were 
observed which have not before been described upon this mineral, viz : 
(031), (051), (061) and (071). 
Artificial Reproduction of Anhydrite from Evaporation 
of Salt Solutions.—Brauns’ has produced anhydrite in r 
1Edited by Dr. Wm. H. Hobbs, University of Wisconsin, Madison, 
? Zeitschrift d. deutsch. geologischen Gesellschaft, xlvi, pp. 50-67, abe 
3 Neues Jahrbuch, f. Min., etc., 1894, (II), pp. 257-264. 
