THE SUCCESSION IX THE MARQUETTE IRON DISTRICT. 5 



This essay desen^es the careful study of every one interested in the history of life 

 on our planet. 



It is well that the Geological Survey of the United States can give to the world 

 such works and can afford a place on its staff and in its laboratories to this im- 

 portant subject. It is to be hoped that it may do this to a still greater extent, for 

 however the study of fossil plants may be advanced by the zeal of independent 

 collectors and students, it requires a national nucleus and means for adequate pub- 

 lication and distribution of its results, and for the safe keeping and proper arrange- 

 ment of those specimens, often so rare, valuable and fragile, which exhibit to the 

 eye the history of plant life from the old Paleozoic times. 



Remarks upon the matter of the President's communication were 

 made by C. D. Walcott, Avho stated that the uncompleted work of Pro- 

 fessor J. S. Newberry would be prepared for publication by Dr Arthur 

 Hollick, and that paleobotanic work was receiving full attention in the 

 United States Geological Survey and National Museum ; Professor Lester 

 F. Ward and Professor F. H. Knowlton being engaged upon the paleo- 

 botany of the Mesozoic and Cenozoic strata, and Mr David White upon 

 the Paleozoic flora. 



The second paper read was — 



ORIGIN OF THE PENNSYLVANIA ANTHRACITE 

 BY J. J. STEVENSON 



This paper will be found printed in full in succeeding pages of this 

 volume. 



The third and concluding paper of the morning session was as follows : 



THE SUCCESSION IN THE MARQUETTE IRON DISTRICT OF MICHIGAN 



BY C. R. VAN HISE « 



lAbstracQ 



As a result of the detailed mapping of the Marquette iron-bearing district of 

 ^Michigan by the Lake Superior division of the United States Geological Survey the 

 following succession has been found to obtain in the iron-producing part of the 

 area : 



Tbe oldest group of the region is the Basement Complex, consisting of granites, 

 gneisses, various green schists and greenstone-conglomerates. The latter rocks 

 appear to be surface volcanics, in part lavas and in part tuffs. The green schists, 

 as well as the mica-schists, hornblende-schists and gneisses, are intruded in the 

 most intricate way by the granite and gneissoid granite. Many of the laminated 

 rocks have been traced into massive phases, so that it is known that many of them 

 are of igneous origin. On the other hand, it has not been possible as yet to show 



