2 University of Michigan 



In pursuing this work^ the writer has become indebted to a 

 number of persons. He wishes to express his obligations to 

 Mr. and Mrs. R. C. Flannigan, especially the latter, for acting 

 as guides on several occasions, and for trips to points aroimd 

 Norway, and for their kind hospitality; also to all of the mem- 

 bers of the party, with Dr. Ruthven in charge, for assistance 

 in collecting and in finding favorable localities for study. He 

 also wishes to thank Mr. G. H. Coons for the identification 

 of many plants from the various habitats, and Dr. V. Sterki 

 for the identification of the Sphseriidae, which were forwarded 

 to him through Dr. Bryant Walker. 



Description of the Region 



The region studied (map facing page 44) lies in about 88° 

 longitude by 46° north latitude, and varies from about 900 

 to 1500 feet above sea-level. The Menominee River forms 

 the boundary line between Wisconsin and the northern penin- 

 sula of Michigan, and of the two localities studied. Sand Port- 

 age and Upper Twin Falls, the first is about two miles south 

 of Norway, Michigan, and the second about four miles north 

 of the town of Iron Mountain. Pine Creek flows along the 

 border of the granitic hills about two miles north of Norway, 

 where Fern Creek enters it from that region. Hanbury Lake 

 is just southwest of the mining town of Vulcan, and the falls 

 of the Sturgeon are about a mile northeast of the town of 

 Loretto. Brown Lake is about eleven miles north of Waucedah, 

 and the places mentioned from its vicinity are all located on 

 the sketch map of that region, with the exception of Foster 

 City, which is about four miles north-northeast of the lake. 



This region is almost entirely underlaid with Archaean and 

 Algonkian formations, although there are patches of Cam- 



