360 MINNESOTA BOTANICAL STUDIES. 
extend for some distance up the narrow dark ravines. In places 
where timber covers the flooded areas the vegetation is similar 
to that of the mud flat on the islands near the river. The vege- 
tation of the open table lands I have called mesophytic field. 
CoLD SPRING VEGETATION. 
The valleys of Winnebago and Crooked creeks have a great 
many springs arising from the bases of the bluffs throughout 
their whole length but perhaps more numerous at the heads of 
the creeks than elsewhere. Some of the springs that outlet in 
low level land occasionally form small cold bogs in which the 
ordinary cold water plants find very favorable conditions for 
growth. A large spring near the head of Clear creek, a short 
branch of Crooked creek contains the greatest abundance of 
typical cold water plants of any spring visited. The large 
creeks do not contain much vegetation. The smaller creeks 
often contain plants similar to those of the cold springs. 
The plants characteristic of cold running water are: 
Batrachium divaricatum, Mimulus gamesiz, 
Batrachium trichophyllum, Philotria canadensis, 
Berula erecta, Roripa nasturtium, 
Cardamine bulbosa, Veronica americana. 
Epilobiums—coloratum and adenocaulon—are often found 
growing in cold spring water but are not peculiar to this local- 
ity as they are also found growing in moist soil. None of the 
spring plants can be called common to large areas, for the con- 
ditions necessary for their growth are limited in extent. 
POND VEGETATION. 
There are but very few natural ponds along the creeks. The 
ponds are generally artificial and as such present a variety of 
conditions and a corresponding variety of plants. A small 
natural pond in a bog near Crooked creek contains all it can 
hold of the yellow pond-lily. (Plate XXVII., B.) This is the 
only place in which any of the water-lily family were found 
outside of the sloughs and lakes of the Mississippi river. 
WET MEADOW VEGETATION OF THE CREEK VALLEYS. 
The wet meadows naturally cover a very large part of the 
creek valleys but under present conditions most of them are 
