1893.] Geology and Paleontology. 997 
igraphic relations of the two rocks along their line of junction. (2) 
The alteration of the sedimentary rocks along the line of junction. 
(3) The inclusion of angular fragments in the mass of the gneiss which 
are clearly referable to the adjacent sedimentary strata. (4) The 
occurrence of gneissic intrusions distinctly irruptive. (5) The absence 
of limestones, slates or quartzites, or any species of rocks indicative of 
ordinary sedimentation. (6) The general character of the rock itself. 
(Bull. Geol. Soc. Am., 1893.) 
The Carboniferous Glaciers of Central France.—In a note 
on the geogeny and stratigraphy of the coal-measures of central 
France, M. A. Julien discusses the various problems to whose solution 
the key is given by the discovery of the glacial origin of the breccia 
in the coal-measures: (1) the cause of the glaciers of the coal-meas- 
ures; (2) their centers of dispersions; (3) the direction of the glaciers 
for each basin; (4) the precise relative age of the breccia. 
The cause of the glaciers is the elevation, at the beginning of the 
Upper Carboniferous period, of Alpine masses forming part of that 
chain which Mr. Marcel Bertrand designated, a few years since, the 
Hercynian chain. The formation of this chain caused the elevation of 
central and western Europe and displaced the carboniferous ocean as 
the Alpine chain, at the close of the Miocene epoch, expelled the Hel- 
vetian sea. In both cases these extensive orogenetic movements were 
accompanied by an enormous development of the internal activity of 
the globe resulting in the breaking out in Europe of that series of por- 
phyritic voleanoes of the Permo-carboniferous epoch, and of trachytic 
and basaltic eruptions toward the close of the Tertiary. It is not, 
` then, at all strange to find traces of Permian and Carboniferous gla- 
ciers since the conditions which produced the more recent glaciers were 
present also during those earlier periods. 
With the aid of a careful lithological inventory of each basin, one 
can infer the height of the original mass, and the direction of the flow 
of the glaciers. For instance, those entering the basin of St. Etienne 
came from the north. 
In regard to the relative age of the breccia, the author concludes 
that the Coal-measures of the basins of Epinac, Blauzy, Brassac, Lang- 
eac, Commentry, etc., are synchronous, that their formation has been 
simultaneous, and that they differ from each other only in having their 
upper beds more or less worn down by erosion. 
M. Julien is thus led to synchronize, in spite of conflicting floral tes- 
timony stated by M. Grand 'Eury, the beds of Rive-de Gier, Valfleury 
and Fouillouse, those of Epinac, Colombier, and Marais, at Commen- 
