Occasional Papers of the Museum of Zoology 17 



small hills and ridges, and many small depressions, often poorly 

 drained. In the damp depressions, if not wet enough for a 

 bog, arbor-vitae and hemlock are common, while on the ridge? 

 sugar maple and linden are characteristic, though hemlock 

 occurs here sparingly also. There is accordingly much local 

 variation in tree forms; but the whole forest is decidedly of a 

 hardwood type. 



The dry hardwood forests of the Little Girl's Point Region 

 are inhabited by many deer-mice, while only a fcAv of this 

 species are found in the wet hardwood forests near Gogebic 

 Lake, bob-tailed shrews being there the most abundant mam- 

 mal and red-backed voles being common, both of which are 

 rare in the other districts. In the dry hardwood forest near 

 Little Girl's Point four woodland jumping mice (Napaeozapus) 

 were taken, while in the Cisco Lake Region only two were 

 taken in a period twice as long, and at Gogebic Lake none were 

 secured. These observations indicate that moisture conditions 

 in hardwood forests have an important influence on the mam- 

 mal fauna. 



Mountains 



Rock-bluff habitat: Rock exposures are rare in the region 

 studied. However, there are several high hills with steep 

 exposures of rock a short distance north of Ironwood arid 

 Bessemer. These hills could not be studied in the tim.e avail- 

 able, and the only cliff examined was on a small rang*^ of hills 

 northeast of the station of Lake Gogebic. On one of these 

 hills is a nearly perpendicular rock cliff about 200 feet high 

 and facing to the southward. The small talus slope at the 

 bottom is overgrown with shrubs and trees, and on the small 

 ledges and gullies of the face of the cliff a few small trees, 

 shrubs, and herbs are also growing. The most conspicuous 

 plants of the rock habitat are scrub oaks, aspens, and heaths. 



