998 The American Naturalist. [November, 
try, of Combelie and of Chaléde in the basins of Brassac and of 
Langeac all of which were in existence before the glacial formation in 
its maximum extension. For similar reasons, he synchronizes also the 
upper beds in the great sterile plain, such as those of St. Etienne, 
Grand-Moloy, and Sully, those of Blauzy, the upper bed of breccia of 
the Carboniferous terrain of Meaulne, and the beds of Brassac and of 
Marsange. 
M. Julien also considers the extensive bed of Commentry parallel 
with the three divisions of St. Etienne (Revue Scientifique, Sept., 
1893). 
Quicksilver Ore Deposits.—An important paper by George F. 
Becker, intended for the use of mining engineers. The first section 
treats of data from observation, the second of theoretical inferences as 
to the transportation and precipitation of the ore and of the form of 
the deposits. In this connection the recent advances in the study of 
osmosis is pointed out. In closing, the author gives a brief résumé of 
recent developments in various parts of the world, in which he embod- 
ies the results of the investigations of Professor A. Schrauf on Idria 
and Mr. P. de Ferrari, on the mines of Monte Amiata. 
Statistical tables accompany the paper compiled from Monograph 
XIII of the U. S. Geological Survey. (Extract from Mineral Resour- 
ces of the United States, Calendar Year, 1892.) 
The Discovery of Miocene Amphisbznians.—No fossil 
remains of Amphisbzenians so far have been made known. Mr. J. B. 
Hatcher, so well known to paleontologists, had the good fortune this 
summer to procure two small Lacertilian skulls, in the White River 
Beds of South Dakota, which when shown to me, I at once recognized 
as belonging to the Amphisbenians. Professor W. B. Scott of Prince- 
ton College, for which Institution the collections were made by Mr. 
Hatcher, had the great kindness to allow me the publication of this 
very interesting find; and I give to-day a short description of the prin- 
cipal characters of the skulls, which will be followed soon by a full 
account with figures. 
1. The larger skull, which measures 13 mm., from the middle portion 
of the condyle to the anterior end of the premaxillary, and 53 mm. at 
its transverse diameter between the posterior ends of the maxillaries is 
so close to Rhineura Cope, from Florida, that I am not able to place 
it with the present material in another genus. 
The nostrils ate spree in position. The single premaxillary is 
widely th tals by the large nasals, which are distinct, 
and extend to the border of the ijare; overroofing the nostrils. The 
