546° REPORT OF COMMISSIONER OF FISH AND FISHERIES. 
cavity. The length of the fish was about 75 mm., that of the parasite 
400 mm. The greatest breadth, near the anterior end, was6mm. For 
the first 75 mm. it was thick and stout, the remainder was slender and 
tapered slowly to the posterior end, near which the breadth was about 
2mm. Several large suckers from the lake were examined, but no 
ligule were found in them. The water of the lake is quite cold, the 
temperature 40° F. having been found at a depth of 124 feet. 
On July 29, I examined a number of suckers collected in Witch 
Creek. The fish were taken in a seine from a warm branch of the main 
stream. ‘The temperature of the water in which the fish were swimming 
was 95° F. A school of fish were observed in the warm stream where 
it joined with a cold stream, 46° I’. The fish showed no tendency to 
enter the cold water, even when frightened by the presence of the seine. 
Two species of fish were secured from this school, viz: Catostomus ardens 
and Leuciscus atrarius. The specimens were all young or half grown. 
No trout were seen in the warm water, although they appeared to be 
rather abundant in the cold stream. 
The larger suckers were nearly all infested with these parasites; the 
smaller ones not so much, and the smallest scarcely at all. Of 30 fish, 
ranging from 14 to 19 centimeters in length, only one or two were with- 
out parasites. Of 45 specimens averaging about 10 centimeters in 
length, 15 were infested and 30 were not. Of 65 specimens, averaging 
about 9 centimeters in length, 10 were infested and 55 were not. Of 
62 specimens less than 9 centimeters in length, 2 were infested and 60 
were not. 
I insert the following notes made at the time of collecting: 
1. Fish 19 em. long, contained 1 parasite, length 39.5em., broadest at anterior end, 
where it measured 15 mm. 
2. Fish 17 cm. long, 1 parasite 27 em. long, 13 mm. broad near anterior end. 
3. Fish 15 cm, long, 4 parasites, 12, 13, 18, and 20 em. long, respectively. 
4, Fish 15.7¢em. long, no parasites, 
5. Fish 13 em. long, 3 parasites. 
6. Two fish 13 and 14 cm., respectively, no parasites. 
7. Fish 11 cm. long, abdominal region flabby and collapsed, a hole beside and a 
little in front of vent from which a parasite had apparently escaped. One 
free ligula was found with the fish when they were brought in. The fish 
may have been injured in seining. The intestine was congested. 
8. Two fish 10 and 11 em, long, respectively, more than one parasite in each; put 
in alcohol entire. x 
9. Fish 10 em. long, no parasites. 
10. Two fish 10 em. long, no parasites, intestine and peritoneum congested. 
11. Fish 10 cm. long, no parasites; intestine and peritoneum black and unhealthy 
looking. 
12. Fish 10 em. long, one parasite 39 cm. long. } 
13. Three fish each 10 cm. long, two with 2 and one with 3 parasites. 
14. Two fish, 8 and 9 em., respectively, one with 3 and the other with 4 parasites. 
The parasitized fish are perhaps a little lighter in cclor than the non- 
parasitized ones. _ 
Pons 
