296 Bibliography. 
part of the now known history of ancient epochs in this hemisphere. 
Among these, is the age of the extensive red sandstone formation of the 
Lake Superior region, which more from its intersection by trap dykes 
rather than frem any other reason, was formerly referred to the same age 
with the Connecticut river red sandstone. It appears to be settled that 
these rocks, as Messrs. Foster and Whitney announced in the first part 
of their Report, are as old as the lowest Silurian. The occurrence of 
Lingula and Trilobites in this group, must be considered, the authors 
observe, as conclusively settling its age. r. an of Canada, from 
Surveys there made, announces that the evidence is clear and indis- 
putably conclusive. 
nd able 
in its science. The author, among the first of American geol 
rocks and fossils of the West, and to the general progress — 
cal science. The volume gives elaborate descriptions of t 
tal formations of the Upper Mississippi, taking up the seve 
order, describing their features, materials, fossils, range, 
~ economical bearing. of Middle 
Next follow Dr. J. G. Norwood’s Report on the Geology %. south 
d Western Minnesota; Col. Whittlesey’s Report on LAbprscwe™ i 
of Lake Superior; Dr. B. F. Shumard’s Report on Geol wid Kettle 
of the St. Peter's, Mississippi, Wisconsin, Barraloo, Sake 
Rivers Dr. Joseph Leidy’s Memoir on the Fossil Mammalia i. 
tilia collected during the survey, in which are descriptions nd add 
new genera as well ag species. An Appendix on the fossils, ~ ' 
tional chemical examinations by the author, with a catalogue most it 
by C.C. Parry, and birds by H. Pratten, close this large and 
portant volume. The quarto volume of plates, contains fifteen 
of geolo’ 
he geolog” 
ra 
extent, and 
