40 PAPERS ON ZOOLOGY OF MICHIGAN. 



vegetation is common in the stream. The bottom is of decayed vege- 

 table matter with a thick cover of plant debris. The stream flows into 

 the lake through a broad embayment which is well overgrown with 

 reeds and flags. 



Maple River, the only outlet to Douglas Lake, is in many ways 

 very different from Bessey Creek. This stream does not flow through 

 a wooded area but through a more open burned-over area. The 

 stream is about twenty feet wide in its widest part and is on an 

 average about two feet deep. Its current is swift but as it flows through 

 a sandy country the water is very quiet. The bottom of this stream 

 is of marl with some vegetation. About two miles from the lake, down 

 the river, collections were made in a situation quite different from 

 the river. The stream at this second station flows through an area 

 from which the trees have been cut or burned as at its source, but the 

 water is swifter and the bed of the stream is of coarse gravel and small 

 rocks. 



Bryant's Bog is a relic bog which has been cut off from the lake bj- 

 the throwing up of. a sand-bar. Although the whole bog occupies about 

 ten acres only about one-half an acre is covered by open water. The 

 water is about 18 feet in the shallowest part. The bog has no known 

 outlet, although there is undoubtedly more or less loss of water through 

 the very sandy, porous soil which surrounds it. The small size and 

 great depth of this bog together with its location in a more or less 

 sheltered place makes the water quiet. The dominant plant about the 

 bog is Chamaedaphne calyculata (Linnaeus) the so-called "leather leaf." 

 On account of its depth few plants grow from the bottom of the pool 

 although the Chamaedaphne grows out into the water about the edge of 

 the bog for several feet. This vegetation in the water makes an ex- 

 cellent habitat for a number of species which are abundant upon the 

 submerged portions. Such species as Tramea lacerata Hagen and Anax 

 Junius Drury were found in numbers in this situation. The low shrub- 

 bery and a few large trees near this habitat supply a very desirable 

 foraging ground for a number of the imagos. 



Smith's Bog, located about two miles south of the Station, is another 

 situation from which a number of specimens were obtained. The 

 marshy area, although called a bog, is quite different from Bryant's 

 Bog. It is located in an open area of about forty acres, the water 

 covering about ten acres. In the water and about the edge of the bog 

 for about one hundred feet is a thick growth of rushes of several species. 

 There are a few trees standing, and over the whole area are old logs 

 lying in or near the water. The depth of the water is probably not more 

 than four or five feet in the deepest parts. Nymphs were found to be 

 abundant in the water while the adults were also common. 



