( 80 ) 
37. Red-jinned Shiner. Luxilus cornutus, Mit. (2.) Chiefly veg- 
etable. Fragments of unrecognizable insects, a mass of confervoid algae 
and parts of a netted-veined leaf. 
38. Silver Fin. Luxilus analostanus, Gir. (3.) Insects of several 
orders and a few algae. 
39. Red Fin. Lythrurus diplaemius, Raf. (1.) A few small dip- 
tera. 
40. Emerald Minnow. Notropis atherinoides, Raf. (2.) Several 
small gnats, an unknown hemipter and a little vegetable matter. 
41. Silver-mouthed Dace. Ericymba buccata, Cope. (1.) A few 
small larvae of diptera, much sand and indeterminable matter, partly 
vegetable. 
42. Common Chub. Semotilus corporalis, Mit. (1.) Many Ephemera 
larvae and a larva apparently belonging to the Dytiscidae. 
SUCKERS. CATOSTOMIDAE. {24.) 
My observations on this family indicate that its food is chiefly animal, 
consisting principally of mollusks, insect larvae and entomostraca. It is 
not impossible that in this, as in some other cases, the proportion of veg- 
etable food is under-estimated, owing to the rapidity with which it is di- 
gested, as compared with the chitinous and calcareous coverings of arthro- 
pods and mollusks. The intestines of the family contain usually large 
quantities of mud. 
There seems to be a well defined difference between the food of the 
Catostominae (Red Horse) and that of the Bubalichthyinae (Buffaloes), the 
former group feeding much more freely on mollusks than the latter, and 
less generally on entomostraca. Of the eight Myxostomas examined, the 
principal food of each was small, thin-shelled Unionidae (Anodonta), 
while no entomostraca at all were observed in them, and annulate worms 
(Naididae) were found in but two specimens. On the other hand, mollusks 
were found in only four out of fourteen carp and buffaloes (gasteropods 2, 
bivalves 2), and in these insignificant in quantity, while large numbers of 
entomostraca were noticed in twelve of the specimens. The intestines of 
many of the buffaloes were filled with a yellowish, shreddy, corpuscular 
fluid which I could only interpret as altered intestinal mucus and broken 
down membrane. The fishermen at Peoria report, however, that these fishes 
frequent the mouths of the gutters from the still-houses of which the river 
front is redolent, apparently feeding upon the distillery slops. 
43. Red Horse. Myxostoma maerolepidotum, Le S. (3.) Chiefly 
mollusks, (Unionidae, Physa, Planorbis.) A number of ringed worms (Nai- 
didae), fragments of Chara and endogenous vegetation, and much mud. 
