518 REPORT OF THE COMMISSIONER OF FISHERIES. 
The kind of parasites and their prevalence in the different parts of 
the alimentary tract were as follows: 
Mouth.) Esopha- stomach. Intestine. 
gus. 
= = z = = | 
AMI seu 0a: R00 st) eee NE SERRE es ror ee ene soe PS) ae 3 3 | Gi eee 
PES OMICS yw hoe jet Toa Sea aOR ee Dee ee he ee eee tee, me | bent See eee 9 27 
IN eS 0a? h 10(0 YC ae eee ee en ae ein nen eet OOo Me qoeoo pamecen een 10 19 
Neamt hocep hala: csc sees =e merase Sat ee eee etale aa oles ere orate) siete reiterate en PaaS 1 
Every fish examined contained some parasites. Cestodes and nema- 
todes were present in more than half, while Acanthocephala occurred 
in but a single fish. It was noticeable that fish caught in April and 
May were much freer from parasites than those caught in November. 
The trematodes were nearly all Azygia tereticolle. One cestode was a 
species of Proteocephalus. 
6. Pomowxis sparoides, calico bass. 
Three specimens of calico bass were caught during July in Lake 
Wingra. They had plankton only as food. The only parasites found 
were two leeches, one on the tongue of one fish and one on the roof of 
the mouth of another, and a few small cysts on the outer wall of the 
stomach. 
7. Ambloplites rupestris, rock bass. 
Sixteen rock bass were caught during May and July in Lake Men- 
dota. The food, found in the 13 fish containing any, consisted of insect. 
larve in 2 and crawfish in 12. The specimens examined by Forbes (6) 
were found to have eaten insect larvyee much oftener than the bass 
from Lake Mendota. 
Three fish were without parasites. In the 13 in which they were 
found the distribution was as follows: Trematodes in 1, nematodes in 
3, and Acanthocephala in 12. Almost as noticeable as the fondness for 
crawfish as food was the prevalence of Acanthocephala; the entire 
absence of cestodes is also noticeable. 
8. Lepomis incisor, bluegill. 
Specimens were taken in March, April, and July from Lakes Men- 
dota and Wingra. Thirty fish were examined, 20 containing food, as 
follows: 
Fish in 
Fish in 
Food. which Food. which 
found. | found. 
Plant tissue, mostly Ceratophyllum.....- 9 | Gammarids: ol. 2 cocoa ase ae 2 
Pls MtO ms a epeee ts. nc oe oeclebles ce ea eeeeaee 13 | Leeche@s;..2 5. Vo. sce eee Eee reas 1 
Jee Um WAVES SopegaaoDOendOu ae OeC uO oStE 9 | Snails, mostly Physa ancillavia.......-- 1 
Thirteen of the fish were entirely without parasites, as far as a gen- 
eral examination showed, and the other 17 contained the following: 
