174 College of Forestry 
Large water snails (Vivipara, Campeloma) and clams 
form a large part of the diet of this catfish, some specimens 
examined having eaten little else. Of this food Forbes (1888, 
b, p. 457) remarks: ‘ Notwithstanding the number of 
bivalves eaten by this fish, no fragments of a shell was ever 
found in their stomachs, but the bodies of the mollusks seem 
to have been separated, while yet living, from the shells, as 
indicated by their fresh condition and by the fact that the 
shell muscles were scarcely ever present. Fishermen say that 
they are often first notified of the presence of catfishes in 
their seines by seeing the fragments of clams floating on the 
surface, disgorged by the struggling captives. Still more 
interesting and curious is the fact that the spiral-shelled 
mollusks found in the stomachs of these fishes were almost 
invariably naked, the more or less mutilated bodies having 
only the opereles attached. The shells are evidently e1 racked 
in the jaws of the fish and rejected before the food is 
swallowed As many as 120 bodies and opercles of water 
snails (Campeloma and Vivipara) were by us taken from the 
stomach of a single Illinois River catfish.” 
Four young examples of this species were found by Forbes 
to have fed principally upon insects, including ( ‘hironomus 
and Hexagenia (eggs and young), with a few crustaceans 
of Daphnia and Allorchestes dentata. 
Ameiurus natalis (LeSueur). Yellow Bullhead. 
The mollusean food of this fish is relatively of small 
amount, forming but 5 per cent. of the ers food. Three 
genera are noted: by Forbes (1888, b, p. 459). 
Vivipara, taken in October. 
Campeloma, taken in October. 
Physa, taken in October. 
On the whole this fish is a scavenger, eating dead animals 
and other debris. Forbes examined 12 adult specimens 
taken from May to November. Vegetation (Lemna and 
Wolffia) formed a very small percentage, fishes about 33 per 
cent., insects (principally Hexagema larve) about 30 per 
cent., and catfishes 17 per cent. 
