MICHIGAN ACADEMY OF SCIENCE. 89 



been published recently by the U. S. Geological Survey, as the area to be 

 studied. It is situated on the south shore of Lake Superior, in a town- 

 ship of the same name, and included between latitude 46° 30 ' and 46° 40 ' 

 north and .longitude 87° 21 ' and 87° 30 ' west. 



The city of Marquette lies on an elevated point between Marquette Bay and 

 Presque Isle harbor. About three miles south of the city is an east and 

 west range of quart zite and granite rocks. Rising ra])idly from the lake, it 

 forms Mt. Mesnard in Sec. 34, T. 48 N., R. 25 W. This mountain range is 

 exceptional in its continuity, since broken chains of irregular hills and 

 short ridges of various sizes, separated by swamps, sand areas and lakes is 

 the prevailing character elsewhere. About four miles north of the city occurs 

 a landspur, known as Presciue Isle, formed by a protrusion of peculiar rock 

 masses (Dolomite) and with considerable cliffs at the north end. 



The region was entered July 9, 1906. After a brief preliminary study it 

 was deemed best to examine the immediate habitat in detail, later to com- 

 pare it with and include examples of other representative environment of 

 the region, and then to make the work a comparative study of types of hab- 

 itat. This method involves, of course, as careful a study of the various eco- 

 logical factors as is usually applied to special problems of field ecology, but 

 lacking time it was thought best to keep in mind a variety of habitats more 

 or less genetically related. 



Beginning therefore, with the harbor of Presque Isle, stops of a few days 

 each, were made along the shore of Lake Superior at points consisting of out- 

 cropping trap rock, of sandy and gravelly beaches, and of sand dunes. From 

 these points observation and study turned to the bogs and swamps back of 

 the sand dunes and inland, and then to the more elevated sand areas near 

 the city of Marcjuette, west of Ridge Street. On July 27 the work continued 

 up Mt. Mesnard, including an open ravine, burned areas and clearings, and 

 the more densely forested regions south of Mt. Mesnard. The remaining 

 time was spent in short trips down Dead River, to Partridge and Middle 

 Islands, to Little and Pickerel Lakes, to Escanaba, Wells, Sands, Negaunee 

 and Ishpeming. 



Although the collection is far from complete, the .specimens collected are 

 nevertheless representative; and the information received from old settlers 

 has jjroved of value. I wish in this connection to express my sincere ap- 

 preciation to Hon. Peter White, of Marquette, i\Ir. Bryant Walker of Detroit, 

 and Prof. F. C. Newcombe for the opportunity afforded me. I am likewise 

 indebted to Dr. Downing of the Marquette State Normal, who has been ex- 

 ceedingly kind, not only in placing at my disposal his collection, but in num- 

 erous other ways as well. Special acknowledgment is due to Dr. C. A. Davis, 

 who, in addition to much friendly and helpful suggestion and interest, very 

 generously has given much of his time to the identification of the plants col- 

 lected. 



Topography.— It is unnecessary to describe the geology and topography 

 of this region, as it has been treated repeatedly by others. For this report 

 it is sufficient to point out that the northern and southern halves of the state 

 are readily distinguished. The upper or northern part consists largely of 

 rugged mountains and hilly regions, some of the hills rising 1450 to 1500 feet 

 a. t. (840 to 900 feet above Lake Superior in the vicinity of Marquette), 

 and hence offers a greater complexity in its geological formations and topo- 

 graphical features. The rocks are usually crystalline or metamorphic, ex- 

 cept near the lake level, where the Potsdam Sandstone appears. Many 

 strata of the various geological epochs are here represented, in some places 

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