Modern Gypsum Deposits — Rowe. . 113 
these beds can be assigned definitely to neither Permian 
nor Triassic. 
Analyses* 
Near Armington, Montana. Near Bowler, Montana. 
CaO 33.101 CaO 33.023 
SO^ 45.939 SO^ 45.935 
Water 20 . 960 Water 21 . 042 
Total lOo.OOO Total 100.000 
REVIEW OF RECENT GEOLOGICAL 
LITERATURE* 
The Geomorpbogeny of the Upper Kern Basin. By Andrew C. Law 
SON. (University of California Publications. Bulletin of the 
Department of Geology. Vol. 3, No. 15, pp. 291-376.) Price 65 
cents. 
This paper gives the results of an excursion into the high 
Sierra at the southern limit of Pleistocene glaciation. The larger 
features of the region embrace (1) a high mountain zone, including 
the summit region anA a sub summit plateau, the last representing 
a partially developed peneplain, (2) a high valley zone, which in- 
cludes extensive areas of the upper Kern basin from 8,000-11,000 
feet above sea level and which represents a second period of par- 
tial baseleveling, (3) the cay on zone the valley of the Kern and its 
tributaries which have been cut deeply into the floor of the plateau 
which comprises the high valley zone. The paper takes up in de- 
tail the erosive work of ice during the Pleistocene. 
Two new hypotheses of general interest are offered in the 
course of the paper. First, that the flattened summits of some of 
the higher mountains represent substantially the contact surface of 
the granite batholith of the Sierra Nevada and the overlying meta- 
morphosed sedimentaries. The discussion seems to leave this as 
an interesting suggestion rather than as a well-supported theory. 
The second hypothesis is that the thirty-mile rectilinear north and 
south course of the Kern valley is determined by a line of rift. 
The discussion leaves this as a much more probable explanation, 
which is especially satisfactory when we are seeing fracture-oriented 
drainage networks evolved by guess-work in other regions. Certain 
peculiar buttress-like forms, kern huts, are explained as due to the 
differential slipping of portions of the west wall of the Kern canj'on. 
No mention is made of more than one glacial period. The Kern 
canyon is U-shaped in its glaciated portion, but professor Lawson 
believes that the glacier had but small share in cutting the valley. 
Hanging-valleys are mentioned but are not considered as evidence 
* Analyses made by W. O. Dickinson, Assistant in Chemistry. 
