170 Scientific Intelligence. 
then the waters which spread the loam, a finer deposit, also came — 
from the same source, operating a little later, and with diminished 
force. 
2. Systematic Geology of the 40th Parallel ; by CuaRENce 
Kine.*—The following are citations from one of the chapters in 
are distinctly outlined by divisional periods of marked unconform- 
ity. Consi as a whole, there is a noteworthy fullness in the — 
the summit of the crystalline Archean series. From the first of 
Cambrian age to the present every important interval of time Is 
recorded in the abundant gathering of sediments, which are with 
singular fullness characterized by appropriate and typical life- 
mined, lies an enormous series of mica gneisses rich in quarts 4 
biotite, orthoclase ordinarily exceeding plagioclase. The earlier 
aplitic gneisses and the later mica gneisses expose about 25,000 
feet each of conformable beds. 
* See the preceding number of this Journal, page 66. 
