430 ANNUAL EEPORTS OF DEPARTMENT OF AGRICULTURE. 



information relative to effective and ineffective ingredients entering 

 into the composition of insecticides for use against certain house- 

 hold insects. 



Also work was completed on a study of the effect of storage, heat, 

 and moisture on the insecticidal value of pj'rethrum, and a paper 

 was submitted for publication in the Journal of Agricultural Re- 

 search under the title, "A Study of the Effect of Storage, Heat, and 

 Moisture on Pyrethrum." 



Aside from the routine work of testing the efficacy of proprietary 

 insecticides, the entomologists have continued the investigations rela- 

 tive to the practical value of a number of substances in the control 

 of certain insects, including tobacco powders, naphthalene, pyrethrum, 

 and sulphur. Exhaustive tests and studies were made of the prac- 

 tical value of the various so-called " nest eggs." A very thorough 

 study was made on the control of chicken lice, chicken mites, and dog 

 fleas, with a view to publication of the results. Field tests of the 

 value of various dust mixtures were continued for the purpose of 

 obtaining further information for use in connection with the enforce- 

 ment of the insecticide act. 



The board has cooperated with the Bureau of Entomology in col- 

 lecting and examining a large number of proprietary preparations 

 recommended for use against body lice and certain other vermin. 

 This work was undertaken to determine the value of these prepara- 

 tions for practical use by the Army and Navy, and many of the tests 

 were made by the Bureau of Entomology on a large scale at Army 

 cantonments. 



In cooperation with the Zoological Division of the Bureau of Ani- 

 mal Industry, tests were made relative to the use of soda lye as a 

 remedy for and preventive against worms infesting hogs. As a re- 

 sult of these tests a " Notice to manufacturers of soda lye " was pub- 

 lished October 6, 1917, in the seventeenth Sertice and Regulatory 

 Announcement of the board, advising that statements on soda lye 

 labels recommending its use as a worm remedy and preventive are 

 unwarranted and should be removed. 



