MICHIGAN ACADEMY OF SCIENCE. 
71 
During f lie past 5 years the survey lias been co-operating with the 
U. S. Geological Survey in the mapping and study of the glacial or 
surface formations of the Northern Peninsula. The field work was com- 
pleted under charge of Prof. Frank Leverett during the summer of 1910 
and a map ou a scale of six miles to the inch is now finished and ready 
for publication. It will show in appropriate colors and symbols the 
distribution of the various classes of soils and the features of glacial 
geology, etc., on an excellent black base. It is planned to issue an edi- 
tion of 3,000 of this map and a new edition of 3,000 of a similar map of 
the Southern Peninsula, which was published in the annual report for 
1907. These maps will be accompanied by a descriptive text by Prof. 
Leverett, written in simple style in order that it may be fully com- 
prehended by the average Michigan farmer. We have now ou file many 
advance applications for this work. It will aid very materially in the 
agricultural development of the unpopulated areas of the Northern 
Peninsula and the northern half of the Southern Peninsula. The publi- 
cation of these maps and descriptive text is timely, in view of the 
awakened interest in agricultural development, especially in many parts, 
of the Northern Peninsula. 
South ern Peninsula. 
Report on the Monroe Formation of Southern Michigan and Adjoining 
Regions. 
The work of Professors Grabau and Sherzer which has been in pro- 
gress for several years has been completed and issued as Publication 2, 
Geological Series 1. This is a monographic report of about 250 pages, 
not including about 100 pages of plates and descriptions of fauna and 
flora. The execution of this work does credit to the ability of the 
authors and the painstaking care with which the work has been done. 
The high praise accorded it by the lay and scientific public is a source 
of much gratification to the Survev. 
Report on the Geology of Arenac County. 
The text of a report on Arenac county, by Prof. W. M. Gregory, has 
been completed and is ready for publication. This report is character- 
ized by the same thoroughness of treatment which marks the volumes 
already published on Monroe, Huron, Sanilac, Bay and Tuscola counties. 
Report on the Geology of Wayne County. 
A report on the geology of Wayne county is in the course of prepara- 
tion by Prof. W. H. Sherzer. This work should be ready for the press 
before July, 1911. We have had many requests for this work in ad- 
vance of its publication. It will treat in a manner easily comprehended 
by the reader of average intelligence of the geology, physiography, soils 
and mineral products of the most populous county of the state. 
Report on the Salt Industry. 
Field work in the preparation of a report on the salt industry of 
the state was begun by Mr. C. W. Cook in June, 1910, and continued 
