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: 
were probably Lepiopomus pallidus. All were taken from the Illinois 
River.—a part of them near LaSalle, in July, 1879,—the others 
from Peoria, in June, 1878. 
The smallest (seven-sixteenths of an inch long) had eaten only 
Daphniide. The next in size (one-half inch) contained Cyclops 
(ninety-eight per cent.) and Chydorus. Nearly the whole of the 
food of the remaining four was Daphniide (ninety-four per cent.), 
including Daphnia pulex. 
‘ Food of the Young. 
My smallest specimens, five in number, ranging from three-fourths 
of an inch to one inch, were taken in August, September and Oc- 
tober, at Pekin, Peoria and Mackinaw Creek, Woodford county. 
Neither locality nor date seems to have made any marked differ- 
ence in their food, the principal elements of which were HKntomos- 
traca and Chironomus larve,—fifty-seven per cent. and thirty-seven 
per cent. respectively. 
A few water-spiders (Hydrachnide) and undetermined Amphipoda 
were the other items. The Mntomostraca were all Cyclops (twenty 
per cent.) and Cladocera (Simocephalus vetulus and americanus, Bos- 
mina longirostris and Pleuroxus dentatus.) 
Nine specimens; between two and three inches long, were caught 
at the same times and places as the preceding, except that one 
specimen from Mackinaw Creek was taken in June, and one taken 
in September was from Clear Lake, Kentucky. The greater size of 
these specimens was indicated by the appearance of a few Neurop- 
tera larve in the food—eight per cent. In other essential respects, 
the food was like that of the foregoing group. One specimen had 
eaten largely of water mites and another of cyprids (fifty per cent.), 
and these elements have therefore greater prominence in the aver- 
ages. Chironomus larve and EKntomostraca now sum up eighty-one 
per cent. . 
In the third group of the young, consisting of seven fishes, be- 
tween two and three inches long, the Chironomus larve remain 
about as before (thirty per cent.), Corixas appear (twenty-five per 
cent.) and Neuroptera larve rise to fourteen per cent. Entoraos- 
traca now fall away to a trifle, and larger percentages of Amphi- 
poda appear. Single fishes had eaten the larve of a gyrinid 
beetle, portions of the polyzoan, Pectinatella magnifica,* Leidy, and 
a earthworm,—the latter probably nibbled from some fisherman’s 
chook. 
These specimens were all from the Illinois River, in June, July, 
October and November. 
*This animal forms the large, translucent masses found in midsummer in the slow 
‘water along the margins of the Illinois River and elsewhere throughout the State, usually 
collected about a stick or a stem of a water-weed, They vary from the size of a walnut 
to that of halfa bushel. The fragments were easily recognized by the peculiar form and 
‘armature of the winter eggs (statoblasts), which are discoidal and bordered with a row of 
slender double hooks, shaped something like an anchor. 
—8 
