UNITED STATES DEPARTMENT OF AGRICULTURE, 
BUREAU OF BIOLOGICAL SURVEY, 
WASHINGTON, O. C. 
October 23, 1914. 
Mr. /Jex Wetmore, 
Marion Hotel, 
Ogden, Utah. 
Dear Mr. Wetmore: 
The expert of the Bureau of Chemistry, who is engaged in the analysis 
of the water sent in by from the vicinity of Salt Lake, suggested yesterday 
that it might be well for us to determine whether or not nematodes have any 
agency, direct or indirect, in the disease which has proved so fatal to the 
water-fowl of Utah, I am of the opinion, fully shared by Doctor Cobb, nema- 
tode expert, that nematodes have no active agency in producing the disease. 
Nevertheless, Doctor Cobb is of the opinion that an attempt should be made 
to ascertain definitely what agency, if any, is played by one or more species 
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of nematodes in producing this or in fact any disease of water-fowl. I am 
sending, therefore, four bottles, one to be used as a graduate, two con- 
taining crystals, and the fourth acetic acid, with which to make a solution 
to preserve the material for forwarding by mail. I do not include formalin, 
which ie called for, assuming that you have that. To collect nematodes it ie 
only necessary t© follow the exact procedure of collecting diatoms, only in 
* vs** ■ **- - ' ■ 
this case you should select if possible aquatic plants upon which the ducks 
are known to feed. It is only necessary to squeeze these into a wide-mouth 
container until you have a reasonable amount of mud or ooze, letting the 
water settle and then treating the ooze with the solution, after which it 
should be mailed according to directions. Doctor Cobb would also like some 
