VOL. II. ] Proceedings of Soctettes: 27% 
bons River. Strangely enough no blob are found in Yellowstone 
Lake or River, which are alive with trout. Why it should go 
where it apparently could not get, and did not go where it might 
easily have been, is indeed a mystery. Geysers occur at various 
points near the shore of the Yellowstone Lake, where there is a 
sudden contrast from ice cold to boiling water. Trout may be 
caught and cooked in the same body of water, almost without stir- 
ring from one spot. In fact, not unfrequently they swim into a 
geyser unawares and are speedily killed. All these trout of the 
Yellowstone Lake and River are infested with a parasite—a cestode 
worm. Itsometimes lodges in the abdominal cavity, sometimes in 
the pyloric caeca or intestines, but most frequently in the muscles. 
For some time we were unable to understand how it was that the 
trout of the Yellowstone Lake were thus infested, while those of 
Jackson Lake were not, but the explanation was at last found. The 
California gull and white pelican are hosts of the adult form of this 
parasite, which lives in their intestines. The eggs of the worm, when 
voided by the birds are eaten by the trout, and developing there into 
the larval stage burrow into the muscles of the fish. 
In an interesting stream known as Crawfish Creek no fish were 
present, but an abundance of crawfish ( Cambarus améellis). Grayling 
were restricted to Firehole River and Gibbon River, which flow to- 
gether. The temperature of the water makes a great difference in 
the size of trout, an extremely cold temperature retarding growth, 
and it is on this account that most of the Yellowstone trout are 
comparatively small in size. 
MEMBERS OF THE CALIFORNIA ZOOLOGICAL CLUB. 
Mrs. Kate D. Adams, 109 Montgomery St., San Francisco. 
H. M. Anthony, 124 Oak St., San Francisco. ue 
Mrs. A. L. Bancroft, 1605 Franklin St., San Francisco. 
Frank W. Bancroft, Berkeley, Cal. 
Oscar T. Baron, Fresno, Cal. 
Dr. F. E. Blaisdell, Mokelumne Hill, Cal. 
A. W. Bowman, Piedmont, Cal. 
_ A. W. Bowman, Jr., Piedmont, Cal. 
Mrs. Katharine Brandegee, 819 Market St., San Francisco. 
Robert B. Brandegee, 253 W- 42d St., New York City. 
Townshend S. Brandegee, 819 Market St., San Francisco. © 
