1893.] Geology and Paleontology. 269 
rhipidopterygians. It is, however, extremely unlikely that these forms 
are fishes, but they are more likely Agnatha.—Bull. Geol. Soc. Am., 
Vol. 3, pp. 153-172. C 
The Loess in Southern Russia.—In his notes on Russian 
Geology Mr. W. F. Hume gives an interesting account of the Russian 
Loess, its character and distribution, together with a theory of its 
origin 
The Russian Loess is a yellowish-brown sandy clay, often rich in 
grains of quartz and mica, and in many places rich in carbonate of 
lime and humus. In lies unconformably on all the principal forma- 
tions. To the west of the Dnieper it conceals the broken and contorted 
gneisses and granites of the Archean axis in S. Ekaterinoslav and the 
Don Cossack country it covers the shales and sandstones of the Carbon- 
iferous, whilst in the more central governments of Kursk, Karkoff, 
and Tchernigov it overlies the Cretaceous and the whole Tertiary 
series. Also along a definite line running to the north of these gov- 
ernments it rests upon the Boulder-clays and sands of the Glacial 
period. From its general appearance Mr. Hume considers the Loess 
of Russia to be more or less coeval with that of Central and Western 
Europe, and the paleontological evidence seems to confirm his view. 
In discussing the origin of the Loess Mr. Hume calls attention to 
the relation, pointed out by Professor Suess between the Loess and the 
Glacial Drift, and gives in detail the theories of Professor Armache- 
vsky and Baron von Richthofen, neither of which is sufficient in itself 
to account for the distribution of the Loess 
In conclusion the author gives the following statement of the proba- 
cle sequence of events: 
1. The Loess particles may be originally derived from the finely 
ground material resulting from the wearing of the subjacent beds by 
the ice-sheet. 
II. The same have been deposited in tundra-like depressions under 
the influence of slowly moving waters or by the action of rivers in 
flood. 
` IIL. This deposit under more temperate conditions dried up, and 
was then suitable material for the redistributive action of the wind.— 
(Geol. Mag., Dec., 1892). 
Sources of the Texas Drift.—Mr. Dumble divides the Texas 
drift area into four districts. First the Trans-Pecos Texas, the valley 
of the Rio Grande, and the Rio Grande Divide. The origin of this 
