a ee 
4 wal? 
_ very abundant species of other families, 
5 
into three groups, inhabiting the river, the lakes, and the 
creeks respectively. These groups are distinguished not by 
the entire presence or absence of certain species, but by great 
differences in their relative abundance. By this means the 
’ groups are readily distinguishable even where there is a free 
open-water connection between their habitats. The charac- 
teristic species of the river are in general of the lowest organ- 
ization, the largest, and doubtless the remotest in origin. They 
range into the Mississippi, and a few still migrate even from 
the Gulf. The fishes of the lakes are, on the whole, of higher 
type and smaller size, while those of the creeks are relatively 
very small and have the highest organization of all. There 
are also, in the river itself, clear water and muddy water 
groups, and their local range may change with the shifting of 
the limiting conditions. For example, when Spoon River is 
high, making the waters of the west side of the Illinois River 
near its mouth very muddy, the fishes of that side are different 
from those of the opposite shore where the water is relatively 
clear; but when Spoon River is low and the Illinois is equally 
clear on both sides no such distinction can be recognized. In 
the spring all these groups are mingled indiscriminately by the 
great breeding migration up stream into shallow water. 
Eighty species of fish were found in or near Havana, the 
families most characteristic of the region being the catfishes, 
suckers, and sunfishes. The minnows are more numerous 
than these families, in species at least, but are comparatively 
few as compared with other localities. There are also a few 
as the gars, dogfish, 
gizzard-shad, yellow bass, sheepshead, and carp. 
Besides this local work on the fishes of the State, two ex- 
tensive wagon trips have been provided for, one made in the 
fall of 1899, and the other in progress at this date. Starting 
from Urbana October 21, Mr. Thomas Large, the Ichthyologist 
of the Laboratory, went with one assistant and a complete 
equipment for work in rivers and small streams through east- 
ern Illinois from Ford and Vermilion counties to Vandalia, 
traversing Douglas, Coles, Moultrie, and Shelby counties, and 
making extensive collections to represent the autumn fishes of 
