96 NINTH REPORT. 



to the water's edge, and the humus conditions along the margin favor a flora 

 such as that found in the forest. The vegetation that lines the gravelly 

 margin consists principally of large mats of mosses and liverworts; very fre- 

 quently found are Filix bulbifera, F. fragilis, Equisetum sylvaticum and 

 others. 



Nearer Marquette, Dead River is a slow, meandering stream, building up 

 a broad flood plain, and emptying into Presque Isle harbor. The flora in 

 and about the stream is not peculiarly characteristic. Inhabiting the damp 

 margin of the water courses and the borders of low woods are found a shrub so- 

 ciety consisting largely of Alder (Alnus incana), associated with several willows, 

 red osier, dogwood, and an undergrowth of sensitive and cinnamon ferns, sev- 

 eral species of violets, St. John's wort (Hypericum Canadense), Solidago ulig- 

 inosa, and a number of grasses and sedges pushing out from the mud- flats 

 into the water. Among these are Juncus effusus, Carex tribuloides, Scirpus 

 cyperinus, Carex viridula, C. riparia, C. filiformis, with Dulichium arundina- 

 ceum, Calamagrostis Canadensis, and others on the dryer portions. The 

 flora of these flats is at present transitional. The deposition during floods, 

 and the accumulation of plant debris as well as the decreased flow of water 

 since the abandonment of a former extensive mill-dam, raise the level of the 

 mud-flats, the dryer conditions supporting successively a cassandra, alder and 

 willow thicket. But wherever the prevailing conditions are favorable for 

 an increase in sedges and grasses, the river's outlet ceases to exist and a 

 meadow results. This is the case in the areas north along the Southeastern 

 R. R. 



The amphibious forms of Dead River grade into distinctly aquatic forms 

 where the slow current gives rise to conditions that usually prevail in ponds 

 and in shallow lakes. The c[uiet water t3^pe consists of Sagittaria, Potoma- 

 getons, Myriophyllum, water lilies and others, which toward the shore become 

 more distinctly zonal in arrangement. 



The flora of Little, Pickerel and other lakes visited, though characteristic, 

 each in its own way, is so similar to that existing in the river, that further 

 description may be omitted in this preliminary report. On the fine sand of 

 the beach of such lakes, Equisetum hyemale is found along with the usual 

 marginal vegetation, and away from the shore an alder thicket often leads 

 into the pine or deciduous forest. Sometimes the grass and sedge society 

 passes into a cassandra zone, and then into an alder society, the extent of 

 the changes in plant arraiigement depending upon various changing con- 

 ditions in the environment. On rocky shores the coniferous and mixed 

 forests of the slopes come down almost to the margin of the lake, grading at 

 once into an aquatic flora. The pools and crevices that occur on outcropping 

 rocks and on bare rocks in exposed places contain a vegetation very similar 

 to that found in a like environment along the lake shore. 



Michigan Military Academy, Orchard Lake, February, 1907. 



LITERATURE. 



L Adams, Ch. A., An Ecological Survey in Northern Michigan. Mich. 

 Geol. Survey Report, 1905. 



2. Agassiz, Louis, T^ake Superior, its physical character, vegetation, etc, 

 1850. 



3. Bailey, L. H., Jr., Limits of Michigan Plants. Bot. Gaz., 1882: 106-108. 



4. Burt, W. A., Catalogue of the Plants Collected in the primitive region 

 south of Lake Superior in 1846, pp. 875-882. See Cooley. 



5. Cooley, D., Jackson's Lake Superior, Washington, D. C. 1849. 



