178 College of Forestry 
Umbra limi (Kirtland). Mud Minnow; Mudfish. 
Forbes (1909, p. 204) examined ten specimens and found 
the food to consist largely of duckweed (Wolffia) and 
unicellular alge. Insects and crustaceans (mainly Entomos- 
traca) made up more than 25 per cent. of its food. Mollusks 
were found to the extent of 5 per cent. in some specimens. 
Physa and Planorbis (taken in July) were the only genera 
noted. Hankinson (1908, Dp: 209) found the food of four 
specimens to consist of entomastracans, green alge, water 
mites, midge larve, Planorbis shells, and miscellaneous 
insects. Two of the fishes were caught in April and two in 
July. 
Esox reticulatus (LeSueur). Chain Pickerel; Green Pike. 
The common Pike or Pickerel of Hlinois (Hsox luctus) 
feeds almost entirely on fishes when adult; a single specimen, 
out of 37 examined by Forbes (1888, b, p. 454), had eaten 
20 per cent of dragon-files. The fishes eaten were sunfish, 
black bass, crappie, gizzard shad, Cyprinide (chiefly 
Notropis hudsonius) and Buffalo fish (Ictiobus bubalus and 
I. cyprinella). A number of the fish eaten are mollusk 
eaters. No records have been seen of the food of Hsox 
reticulatus, and while large individuals probably do feed on 
fish, small or young specimens 10 to 16 inches long feed 
almost entirely on crawfish. 
The data from five individuals is shown below, all caught 
in Frederick Creek, above the railway bridge, Constantia, 
with seine, September 8, 1915. The food of these is stm- 
marized below for comparison with those from Green Lake, 
Jamesville, N. Y. (see p. 201): 
COMMDOTUSteane area eee eet cee on tear ree ae 75 per cent. 
STE UES CRDEeE PORRO De Ge ne SCE eRe MEAN PRS. oe 25 per cent. 
No. 1 (142). 280 mill long. 
Remains of crawfish (Cambarus bartoni robustus) in 
stomach; 2 gastroliths 7.50 mill. in diameter. In- 
testine filled with jelly-like mass of digested matter. 
