116 PAPERS ON ZOOLOGY OF MICHIGAN. 



finger {PoteniiUa palusti-is), rosemary {Andromeda sp.), cotton grass 

 {Eriojphorum virginicum) , and high huckleberry (Gaylussacia sp.). 

 Willows formed patches and borders. Tamaracks {Larix laricina) 

 with spruces formed thick swamps and also grew singly over themarsh. 

 Many of these tamaracks were dead (Plate XVIII). 



Where the marsh lakes touch tamarack or spruce-cedar swamps, 

 their shores are wooded (Plate XXIIA). The oldest, thickest swamps 

 and those with largest trees are near the Nipissing bluff. These are 

 quite extensive near Vermilion and contain besides spruces many white 

 cedars, Avith birches, maples, mountain ashes, and many tamaracks 

 forming marginal growths. These swamps have wet, soggy floors or 

 small pools or streams with hummocks, exposed roots, fallen trees or 

 limbs. Sphagnum sp. and other mosses thrive here with many pitcher 

 plants, ferns orchids and other forms. About the edges of these 

 swamps, thick undergrowth is commonly present with such plants as 

 high huckleberry, cotton grass, willows, sweet gale and rosemary con- 

 spicuous. 



Invertebrates. 



As with the plants, only those invertebrates most closely related to 

 the fish life in an ecological way were given particular attention ; these, 

 of course, are those which are aquatic or have aquatic stages. Insects 

 were observed in largest numbers. Some very noticeable ones are 

 biting flies, about the size and general appearance of house flies, which 

 are exceedingly numerous, much more so near Lake Superior. In ap- 

 pearance and behavior, they are like stable flies (Stomoxys calcitrans); 

 and it is possible that they are this insect,- since a specimen of the species 

 was found in a small collection of insects made along the lake shore. 

 Mosquitoes are very numerous, and they were most in evidence about 

 the lowland marshes, toward evening. A few specimens collected 

 proved to be Culex sylvestris, Culex suhcantans, and Anopheles quad- 

 rimaculatus. A number of kinds of dragon-flies and damsel-flies, 

 swarms of gnats, small, annoying tabanide, and many moths, and 

 butterflies, were the most conspicuous of the aerial insects. On the 

 water surface were gyrinids, water striders, and other insects with some 

 spiders. On floating water lilies were seen leaf-eating beetles {Donacea 

 sp.) and frequently large, slender, naked caterpillars (Bellura sp.), that 

 eat the channels in these leaves and mine their petioles (Welch, 1914). 

 Tiger beetles are common .on Lake Superior beach. Some caught there 

 are Cicindella hirticoUis. Beneath the surface in the marsh lakes and 

 in the beach ponds were found many insect larvae and some adults. 

 A list of those collected is here given: 



May-fiies: Heptagenia. 



