REVIEWS 733 
and the Cretaceous floras of the Potomac and Shastan Series, and of the 
Kootanie (Montana), Lakota (Black Hills), and Trinity (Texas) forma- 
tions. Crowe W: 
Geological Survey of Ohio. By EDWARD ORTON, JR., State Geologist, 
Bulletin Nos. 4 and 5, Fourth Series. Columbus, Ohio, 1906. 
Contains: ‘‘The Limestone Resources and the Lime Industry in Ohio,” 
by E. Orton, Jr., and S. V. Peppel, and ‘‘The Manufacture of Artificial 
Sandstone or Sandlime Brick,” By S. V. Peppel. 
The Differentiation of a Secondary Magma through Gravitative 
Adjusiment. By Rercrinatp. A. Daty. Separate from the 
Festschrift zum siebzigsten Geburtstage von Harry Rosenbusch, 
gewidm. v. seien Schiilern. Stuttgart: E. Schweizerbartsche 
Verlagsbuchhandlung, 1906. Pp. 201-32. 
This paper is similar to an earlier one’ by the same author, but con- 
tains a fuller description and new chemical analyses of the Moyie Sell in 
the Purcell Range of British Columbia. This great sill, 840 meters thick, 
is composed of hornblende gabbro grading upward into granitite which 
lies along the upper surface with a thickness of about 45 meters. The 
latter rock is thought to have been derived by assimilation of the country 
rock (quartzite) in the gabbro, and subsequent segregation of the lighter 
granitic material at the top of the sill. CoWa WW. 
The Champlain Deposits of Northern Vermont. By C. H. Hircu- 
cock. (From the Fijth Report on the Geology of Vermont, by 
PROFESSOR G. H. PERKINS.) Pp. 24. Montpelier, Vt., 1906. 
According to the author it is easier to invoke the glacial dam to account 
for the various Pleistocene beaches, benches, wave-cut notches, and sea 
cliffs than to appeal to changes of level. Glacial Lake Champlain may 
have been from 200 to 300 feet higher than the marine limit. Glacial 
Lake Memphremagog discharged through the Elligo pond col into the 
Lamoille Valley and was tributary to Glacial Lake Champlain. 
C. W. W. 
New Forms of Concretions. By HENRY WINpDSoR NicHots.  Publi- 
cation 111, Geological Series, Field Columbian Museum, Vol. 
III, No. 3. Pp. 25-54; plates IX-XXVII. Chicago, 1906. 
t “The Secondary Origin of Certain Granites,” American Journal of Science, 
Vol. XX, pp. 185-216. 1905. 
