24 
“Mix thoroughly, and give from a heaping teaspoonful to 
a tablespoonful, according to the size of the animal, in the 
food three times daily. It will, probably, require consider¬ 
able time for the animal to recover somewhat of its former 
vigor, and good nutritious food is to be depended on more 
than medicine.” 
The following letters from Dr. Riley explain the parasites 
that infests the loco. 
United States Department of Agriculture, 
Division of Entomology. 
Washington, D. C., July 24,1890. 
ProfeRsor David O'Brine’, Agricultural Experiment Station, Fort Collins, Colorado, 
Dear Sir :--I have your letter of July 14, and the fruit of the “loco weed,” 
with the contained larvae. 
This insect seems to be a weevil of the genus Bruchus, allied to the common 
Bean and Pea Weevil; but it will be impossible to determine the species without 
rearing the adult. It is very interesting matter, and I trust that you will send me 
on more of these fruit from time to time. 
Hoping to hear from you again, 1 remain 
Yours truly, 
C. V. Riley, 
Entomologist. 
U. S. Department of Agriculture, 
Division of Entomology. 
Washington. D. C., December 6th, 1890. 
Dr. David O'Brine, Agricicltural Experiment Station, Fort Collins, Colorado. 
Dear Sir :—Yours of the 4th inst. has just come to hand. I am thoroughly 
convinced that the insects which infest the loco weed have nothing whatever to do 
with the effect of this plant upon live stock. The loco weed has a number of in¬ 
sect enemies in which I have been for some years quite interested. It is a common 
thing for persons to suppose that the insects might cause the trouble rather than 
the plant. I shall always be glad to hear from you further and should especially 
like to get some more specimens of the Bruchus which you sent last year. 
Yours truly, 
C. V. Riley, 
Entomologist. 
The following table gives the ash analyses of the loco and 
larkspur : It explains itself. 
