RI12, 1559. Y0L. HI, No. 4. 
THE 
AMERICAN 
A MONTHLY JOURNAL OF 
GEOLOGY AND ALLIED SCIENCES. 
EDITORS AND PROPRIETORS: 
Prof. Samuel Calvin, University of lorva, Iowa City, Iowa. 
Prof. Edward W. Claypole, Buchtel College, Akron, O. 
Dr. Persifor Frazer, Franklin Institute, Philadelphia, Penn. 
Dr Tew is E. Hicks, University of Nebraska, Lincoln, Neb. 
Mr. Edward O. Ulrich,- Geol.,Survey of Illinois,Newport, Ky. 
Dr. Alexander Winchell, University of Michigan, Ann Arbor, Mich. 
Prof. Newton H. Winchell, University of Minnesota, Minneapolis, Minn. 
p/timbers, 35 <$ei}ts. Yearly Subscription $3.50. 
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PAGE 
moir of Mr. G. Featherstonhaugh. 
[Portrait.] J. W. Featherstonhaugh.. . 217 
ERICAN PETROGRAPHICAL MICROSCOPES. 
! [Illustrated.] N. H. Winchell . 225 
THE RELATION OF THE DEVONIAN FAUN¬ 
AS of Iowa. H. S. Williams . 230 
ELIMINARY DESCRIPTION OF N*EW LOWER 
Silurian sponges. [Illustrated.] E. 
0. Ulrich.. . 233 
CENT OBSERVATIONS ON THE GLACIATION 
'of British Columbia and adjacent 
regions. Geo. M. Dawson . 249 
nglomerates in New England gneis- 
i ses. C. H. Hitchcock . 253 
nglomerates enclosed in gneissic 
terranes. [Supplement.] Alexan¬ 
der Winchell... . 256 
utorial Comment. 
The building of the British Isles_ 262 
Review of Recent Geological Litera¬ 
ture. 
Brachiospongidae: A memoir on a 
group of Silurian Sponges, Beecher, 
268.—On the ophiolite of Thurman, 
Warren Co., N. Y., Merrill, 268.—A 
deadly gas-spring in the Yellowstone 
National Park, Weed, 269.—Geological 
survey of Arkansas ; second annual 
report, Branner, 269.—Texas geologi¬ 
cal and mineralogical survey; first 
report of progress, Dumble, 270.—Les 
modifications et les transformations 
des granulites du Morbihan; par 
Charles Barrois, 271. 
Recent publications .... 272 
Correspondence. 
Observations on three Kinderhook 
fossils, R. R. Rowley, 274.—Foliation 
and sedimentation, A. C. Lawson, 276. 
Personal and Scientific News. .. 278 
THE AMERICAN GEOLOGIST, MINNEAPOLIS. 
sneral European Agent, W. P. Collins, 157 Great Portland St., London W. Eng. 
Entered at the Minneapolis post-office as second-class matter. 
