ECOLOGICAL STUDY OF BRUSH LAKE. 165. 
Echinochloa crus-galli (1,.) Beauv. Solanum nigrum L,. 
Panicum capillare L. Ambrosia artemisiaefolia I,. 
Polygonum pennsylvanicum L. Leptilon canadense (I,.) Britt. 
Phytolacca decandra L. Carduus lanceolatus L. 
The Phytolacca did not extend very far beyond the shrub 
zone. In and outside of the shrub zone, which was composed 
mainly of Cephalanthus, willows, dogwood and rose, there was 
an abundance of sedges belonging mainly to the species— 
Carex lupulina Muhl. Carex muskingumensis Schw. 
‘« squarrosa L. 
As stated above, in and about this sedge society and extend- 
ing down to the narrow shrub zone there is a remarkable zone of 
young saplings and seedlings of Fraxinus americana L., forming 
almost a continuous circle around the shallow bank of the filled 
pond. ‘These trees have probably developed within recent years 
since the pond has practically become extinct. The forest zone 
just outside of the sapling zone is rather dry and mesophytic and 
consists of elms, ashes, cottonwoods, oaks, hickories, hackberries, 
dogwoods, etc. 
In the spring of 1903 there was a partial reversion to former 
conditions. A long period of abundant rains had filled the dry 
basin, flooding even the shrub zone; and the surface of the pond 
was diversified by an abundance of the green leaves of Nymphaea 
advena Sol. One visiting this spot for the first time would never 
have dreamed of the moist-ground weed society which had cov- 
ered the place eight months before. With the return of the 
water the pond lillies revived, although had the dry season con- 
tinued for a year longer they would probably have mostly 
perished. 
In this pond there will be an oscillation between hydrophyte 
and mesophyte societies for many years tocome. But finally the 
last pond lily will disappear, having struggled not only against 
living enemies, but against the inevitable change in the physio- 
graphic conditions. ‘The surface of the pond will then be rapidly 
covered by a mesophytic forest, if man does not overrule the 
orderly process of nature. At some distant day Brush Lake will 
be in the same condition as the dying pond and only the spade or 
drill will reveal the former existence of the present basin with its 
hydrophytic flora. 
