128 NINTH REPORT. 



not seen although a very conspicuous and easily recognized plant, and one 

 well known and constantly looked for. It was not observed in the vicinity 

 of Bessemer, nor around Houghton, where conditions were favorable for its 

 growth, ]3ut near Marquette, for the first time, it was seen somewhat fre- 

 quently in the hardwood forest. Late in that season, during a short stay 

 at Newberry, and a rapid reconnaisance over the region between the rail- 

 road and Lake Superior, the species was not observed in the old hardwood 

 forest, or at all, until within five or six miles of Lake Superior, when it sud- 

 denly became a common member of the lower story of the forest, and con- 

 tinued so until the vicinity of the shore of the lake was reached, where pines 

 generally replaced the broad-leaved trees. In returning to Newberry, by 

 way of Grand Marais, after a trip of some thirty miles along the beach, the 

 road which was followed ran almost continuously through a hardwood 

 forest, the Hard Maple and Birches being the dominant species. On this 

 trip the species under discussion was abundant for a distance of five or six 

 miles from the lake, and then was seen no more, disappeariag entirely from 

 the woods. 



In 1906 a more extended opportunity presented itself to study the region 

 from Marquette north and west, covering a large part of Marquette county, 

 and again it was found that while Acer Pennsylvanicum was of common 

 occurrence in the hardwoods, in the vicinity of Lake Superior, it did 

 not appear in similar places which were a few miles inland. In like man- 

 ner, in going from Huron Mountain southward into the highland lying in 

 that direction, the species was not seen after the head of the Mountain Lake 

 was passed, although frequent in the woods nearer Lake Superior; this is 

 about six miles south of Lake Superior, and it was not seen in the heavy and 

 undisturbed forests farther south, about the headwaters of the Yellow Dog 

 river, nor in the great areas of practically unbroken forest in the vicinity 

 of, and to the Avest of Lake Michigamme. 



The habitat of this interesting species is the dense shade of the hardwood, 

 or mixed hardwood and conifer forest, on well watered, but not wet, slopes 

 and flats, where it grows associated with the over-shadowing Birches, Sugar 

 Maples, Basswoods, Elms, and freciuently, also, the somber Hemlocks, 

 often the only undergrowth, a site for which its broad leaves and spreading 

 top especially fits it. With it, in less dense shade, the Mountain Maple is 

 frequently found and young individuals of its taller growing neighbors. 



It is apparent from these obseryations, that Acer Pennsylvanicum is a 

 plant of rather restricted range in the Northern Peninsula, being confined 

 to a belt not more than six miles in width, along the shores of Lake Superior, 

 on the northern side of the Peninsula, and of undetermined limits on the 

 suothern side. Its hal^itat, so far as observed, is also restricted to rather 

 dense shade, and moist, well drained soil. 



Ann Arbor, March, 1907. 



