PUBLISHED MONTHLY. COMMENCED JANUARY 1888. 
Th e /\merican ©eolo^ijt, 
ILLUSTRATED. ^ 
A strictly Geological Journal. 
Two volumes of 400 p^ges each, per year, 
Sufascriptian $3.5D Far Year. 
All back numbers and the subscription for (890, |8.oo. 
EDITORS AND PROPRIETORS. 
Samuel Calvin, Iowa City, Iowa. 
Edward W. Claypool, Akron, Ohio. ' 
John Eyerman, Easton, Pa. 
Persifor Frazer, Philadelphia. Pa. - Robert Junction City. Kansas. 
Clarence L Herrick, Cincinnati,' 0 Arthur Lakes, Golden, Col. 
Andrew C Lawson, Ottawa, Ont. Edward O. Ulrich, Newport, Ky. 
. . 1 . C, White, Morgantown W Va 
Alexander Winchell, Ann Ai bor.. Mich. \ 
Newton H. Winchell, Minneapolis, Minn. , 
Published at Minneapolis, Minn, 
BAU^Cp \ LOMB OpTI^L 
MANUFACTURERS OF 
Microscopes, Objectives 
And Accessories. 
Photographic Lenses, 
AND OTHER 
Optical Instruments. 
Factory. and Main Office, 
N. St.. Paul St. 
Rochester, Nl Y. 
P. O. Drawer 292 
Branch Office. 
48-50 Maiden Lane, 
New York City 
P. O. Box 432. 
I2th Edition , of Illustrated Catalogue free bn 
application. 
New Petrographical Microscope — Made by advice 
and assistance of Prof. Geo. H. Williams, Johns , Hop- 
kins University. 
