516 REPORT OF THE COMMISSIONER OF FISHERIES. 
as compared with those taken in the deeper water, the latter using 
plankton for food much oftener and in greater quantities than the 
former. <A distinct difference was also found in the food of the perch 
living near the shore and those caught during the winter through the 
ice. These latter were taken well out in the lake, and were so differ- 
ent from the others in food contents and scarcity of parasites that 
they are entitled to special mention. 
The scarcity of literature on the food of fresh-water fishes is very 
noticeable, and we could find but little Information on the subject. 
When one considers the amount of work that is being done by the 
federal and state fish commissions in stocking our inland waters, it 
is surprising to find that so few observations have been made and 
recorded concerning any of the important economic questions bearing 
on this subject. 
In classifying our fishes we have followed Jordan and Evermann. 
1. Lepisosteus osseus, gar pike. 
A single specimen of this fish was obtained in October from Lake 
Mendota. No food was found in the alimentary tract. Two cestodes 
and a few small trematodes were present, none of which has yet been 
identified. 
2. Améia calva, dog-fish. 
Thirteen specimens of dog-fish were examined, 4 of which were 
without any food; 7 of the 9 in which food was found contained eraw- 
fish, the other 2, minnows. 
Parasites were very prevalent, every fish having them in considera- 
ble numbers. The following table gives the kinds of parasites found, 
the parts of the host in which they occurred, and the number of fish 
in which each kind of parasite was found: 
Mouth. Stomach.| es Rectum. 
TNTEMMAOMECS. . oser= cia /cleyecisic wer cies aieime a rac oe eek ater nen se aeceree 5 6h) 2s sce Baee | semoisetseer 
C GYe} (0) 5 ct ees pe ae a Se ae ie See ee ees tse bea mats ets 13 13) | a2seeeeeer 
IN@matod 69.2 352 Se cee Seo see Bae re cio aie os eels menieestneesiiacsiccl aise = cisoee ye sete LD | eochegeeee 
AGanthOCephala 2s< ec -tecumtecmn woe ence cee ce ee reweccisie sine Genie] siteeiee eis smteeeeeene iz 1 
WWE C CHES agen esc cineoaj cane eceee aieisoays teense ees Oee ane eeras Toca eee oe \is Stree seed ol cee eee 
The trematodes were all Azygia tereticolle, which fluke was also 
present on the gills of 2 fishes. One fish had an encysted cestode in 
the spleen. 
The prevalence of cestodes was noticeable, they being found in every 
fish examined and in great abundance, 100 to 300 occurring in many 
of the fish. There were at least 2 species of cestodes and 2 species of 
Acanthocephala present. The frequent occurrence of cestodes in the 
stomach was due to the fact that many which were found in the intes- 
tine were fastened to the wall of the stomach, stretching from there 
