PUBLICATIONS RECEIVED. 301 
Professor Rose’s investigations shew, also, that although arragonite generally 
results from crystallization at high temperatures, yet, in concentrated solutions, 
erystals of calcite, at these teniperatures, are equally capable of formation. This 
fact, as observed by the author, is not without important bearings on some of the 
natural conditions of oceurrence of eale spar. Ueber die Umstdnde unter denen 
der Kohlensawre Kalk sich in seinen heteromorphen Zustinden als Kalkspath 
Arragonit, und Kreide abscheidet.— Pogg. Ann. Januar, 1861. E. J.C. 
PUBLICATIONS RECEIVED. 
Descriptions of New Species of Crinoidea, from Investigations of the Iowa 
Geological Survey. By James Hall. Albany: February 25, 1861.—The publi- 
eation of the concluding portions of the Reports of the Geology and Paleontology 
of Iowa being for a time suspended, Professor Hall has issued these descriptions 
in order to claim priority for various new species that may probably appear under 
other names in the forthcoming Report on the Geology of the neighbouring State 
of Illinois. In addition to numerous crinoids belonging to the genera Actinocrinus, 
Platycrinus, &c., two new star-fishes are described. 
Observations upon the Geology and Paleontology of Burlington, Iowa, and its 
Vicinity. By Charles A. White——This is an interesting article reprinted from 
the Boston Journal of Natural History. The rocks described, range from the 
Chemung beds (Devonian) to the Burlington Limestone of the Carboniferous 
group ; and in addition to classified lists of fossils, notices of seven new species 
of Devonian Brachiopoda are given. 
On certain Theories of the formation of Mountains, By E. Billings, F.G.S. 
Notes on the Geology of Murray Bay, Lower St. Lawrence. By J. W. Dawson, 
LL.D., F.G.S.—The above are valuable reprints from the Canadian Naturalist 
and Geologist. This journal, so ably conducted in itself, and so faithful an ex- 
positor of the natural history of the Province, fully deserves the strongest en- 
couragement and support. 
On the Amounts of Lead contained in Silver Coins. By C. W. Eliot, and Frank 
H. Storer—lIn this pamphlet, reprinted from the Proceedings of the American 
Academy of Arts and Sciences, the authors give the results of their examination 
of various silver coins from American, Spanish, English, and other mints. Small 
amounts of lead were found in nearly all: the highest (—°3846 per cent.) in 
some English shillings of 1816. A tive-frane piece of Napoleon III. yielded also 
a comparatively high amount (= 3546 per cent). In connexion with this subject, 
the authors discuss the causes of the impurity in question, more especially as 
regards the United States coinage, and offer various practical remarks of much 
interest, 
Ninth Supplement to Danas Mineralogy. By Geo. J. Brush, Professor of 
Mineralogy in Yale College.—In the regretted indisposition of Professor Dana, 
the preparation of the half-yearly supplement to that author's System of Mineral- 
ogy has been again undertaken by Professor Brush. The present supplement 
contains a list of the principal publications issued since the date of the last or 
VAs ll Ww 
