14 PAPERS ON ZOOLOGY OF MICHIGAN. 



in length. As in all of the lakes of this densely forested region south 

 of Houghton, the water has an umber color, and the bottom material 

 of the shoals is similar to that found in the shallow water of the other 

 lakes — a firm sand tinged with the color of the water. 



The lakes were examined and a number of collections made on August 

 25. No detailed study of the vegetation was attempted, but the fol- 

 lowing plants of special interest were noted: 



Marchantia polymorpha L. — Growing in abundance on beaches. 



Drosera rotundifolia L. — Abundant on the shore and extending out 

 on partly floating logs. 



Equisetum fiuviataU L. — Growing in patches, and in places forming 

 distinct zones along the water's edge. 



Ericaulon articulatum (Huds). — Forming patches on the bottom in 

 shallow water. 



Myrioyhyllum Farwellii Morong. — On submerged portions of logs. 



Potomogeton sp.? — In patches in deeper water. 



Brasenia Shreheri Gmel. — In patches. 



Gloiotrichia Pisum (Ag.) Thuret. — An alga forming gelatinous 

 colonies in shallow water. 



Conspicuous aquatic invertebrates noted were : 



Spo7igiUa lacustris (Linn.). — On brush and other submerged objects 

 near shore. 



Macrohdella decora (Say). — Apparently the common leech of the 

 northern lakes about Houghton. 



Caddice worms.- — Common on the bottom of shoals. Their cases 

 were made of sticks. 



Two amphibians occurred in some numbers around the shores, Raria 

 septentrionalis Baird and Rana pipiens Schreber. 



The fish observed were : 



Chrosomus erythrogaster. — Abundant in schools in both lakes. 



Pimephales promelas. — Abundant in large schools in both lakes. 



Couesius plumheus. — One taken in the south lake. 



Catostomus commersonii. — One caught in the south lake. 



Pygosteus pungitus. — Eight taken in the middle lake. 



Eucalia inconstans. — Two found in the middle lake. 



South Twin Lake. This lake is located about three miles northeast 

 of Winona, on the Copper Range Railroad. It is somewhat over a 

 mile long and a half mile wide, and receives several small streams. 

 The outlet (Plate VIII) is Misery Creek, which flows to the west into 

 Lake Superiol- (Fig. 1). The lake is completely surrounded by the forest 

 except for a small clearing about the single building on its shore (Pl^te 

 II). A well-marked beach, continuous ^\dtll a broad shoal of compact 



