152 
part of May would be far more enlightening than any descrip- 
tion that might be given. As we leave the sandy shore of 
Quiver we traverse the clear, cold, and spring-fed water along 
the eastern bank with its rapidly growing carpet of Cerato- 
phyllum, and in a few rods note the increasing turbidity, rising 
temperature, and richer plankton of the water which has moved 
down from the more or less open and slightly submerged 
bottom to the north (PI. II.). As we cross the muddy bank of 
Quiver ridge and enter the main channel of the river we find 
rougher water, caused by the wind which usually sweeps up or 
down the stream with considerable force between the bordering 
forests. The water also appears much more turbid by reason 
of silt and plankton, and no trace of vegetation is to be seen 
save occasional masses of floating Ceratophyllum or isolated 
plants of Lemna, Wolffia, or Spirodela. Huge masses of cattle- 
yard refuse, veritable floating-gardens, may also at times be 
seen moving down the channel or stranded in some eddy along 
shore. As we plunge into the willow thicket on the western 
shore we have to pick our way through the accumulated drift 
lodged in the shoals or caught by the trunks of the trees or the 
submerged underbrush. The surface of the water is one mat 
of logs, brush, sticks, bark, and fragments of floating vegeta- 
tion, with its interstices filled with Lemnacee dotted with the 
black statoblasts of Plumatella. From this dark labyrinth we 
emerge to the muddy but quiet waters of Seeb’s Lake with its 
treacherous bottom of soft black ooze. We next enter a wider 
stretch of more open territory with scattered willows and ma- 
ples and a rank growth of semiaquatic vegetation, principally 
Polygonums. The water is clearer and of a brownish tinge 
(from the diatoms), while mats of alge adhere to the leaves 
and stems of the emerging plants. A flock of startled water- 
fowl leave their feeding grounds as we pass into the wide ex- 
panse of Flag Lake. We push our way through patches of lily- 
pads and beds of lotus, past the submerged domes of muskrat 
houses built of last year’s rushes, and thread our way, through 
devious channels, among the fresh green flags and rushes just 
