386 Wisconsin Academy of Sciencesy Arts, and Letters. 
in table 2. It is curious that the plants of Green Lake show in all 
cases a slightly higher percentage of water than those of Mendota, 
although the method of determination was as nearly as possible the 
same in both cases. 
The Flora 
A list of the species collected is given in table 1. 
Most of the genera are the same as those found in Mendota. 
There are more species of Potamogeton in Green Lake and a few 
genera not reported in Mendota. The list given does not pretend 
to include all of the species present in the lake; it shows only the 
predominating ones. Identification of rare forms was not thought 
to be of value in a quantitative study. Some other species may 
therefore be included in the quantitative data, among the ones 
named, with those they resemble most closely. 
The dominant plant is Chara,—which in Mendota forms only a 
small fraction of the total vegetation. Chara grows almost every¬ 
where in Green Lake, sometimes mixed with other plants, often 
forming great masses in which no other form can get a foothold. 
Badicula aquatica deserves special mention. This plant was 
found only in two places (see table 4). It is usually described as 
having two kinds of leaves, the immersed ones pinnately dissected 
into capillary divisions, the emersed entire, serrate, or pinnatifid. 
In Green Lake the plant seems never to reach the surface and flow¬ 
ers were not observed; yet there are these two sorts of leaves, both 
under water (it was collected at a depth of two or three meters). 
The shape of the leaves would seem, therefore, not to be determined 
directly by the medium in which it grows. It may be conditioned 
by the intensity of the light. 
Drepanocladus pseudo-fluitans, a moss, not collected in Men¬ 
dota, grows in deep water at low temperatures, and in a few places 
forms immense mats or beds of close-growing stems and leaves, into 
which one may sink to the knees. Apparently it does not fruit in 
the lake, but depends wholly upon vegetative methods of reproduc¬ 
tion. 
Castalia is found in large quantities in Dartford Bay and the 
outlet and in the little bay behind Terrace Beach (Station 41). 
Nymphaea occurs at the other end of the lake, behind Blackbird 
Point; but in the open water of the marshes through which runs 
