Geology and Natural History. 73 
_also the following: Classification of Coals, by P. Frazer, Jr.; 
Firebrick tests, by F. PLarr; Notes on dolomitic limestones, by 
. Puatr. The 
by their number and character indicate a great amount of excel- 
lent work. They are accompanied by descriptions, and often see- 
tions, of the beds from which the specimens were taken e 
of Lawrence County, in which numerous careful sections are 
given of the coal beds and associated rocks, the results of a spe- 
cial study on this subject are brought out. The same point, but 
for a different part of the border region, is illustrated also in the 
Report of Mr. Chance, who surveyed “the Slippery Rock, She- 
nango and Beaver River valleys,” in 1875, “for the special pur- 
ps of connecting the well-known Coal-measures of the Ohio 
iver valley with the then almost unknown or very ill-understood 
rocks of Northern Butler and Mercer Counties. The same prob- 
lem has been studied also by Mr. Ashburner, whose results will 
appear in a Report now in the press. These different observers, 
according to Professor Lesley, agree closely in their results, and 
thus the settlement of this question in inter-State geology is essen- 
tially accomplished. 
Geological Survey of California. Mr. Goodyear sailed about the 
end of September for his new field of labor. 
4,.A 
General Introduction on the Principles of Paleontology ; by H. 
edition, revised and greatly enlarged. 2 vols. 8vo, 1879. Edin- 
burgh and London, (Wm. Blackwood & Sons).—This second 
wood by the author. The author’s acquaintance with general 
zoology, and his labors among fossil corals and other inverte- 
