74 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 10 



lousy at the incubating period. For the young chickens a httle sweet 

 oil is a practical control measure owing to the tenderness of the skin. 



Mercurial ointment is by no means a new insecticide as it has been 

 used for years in the control of Pediculidse. It has been used also in 

 Denmark and other European countries on cows for cattle lice. Its 

 value as an insecticide for hen lice has as yet not been widely known, 

 yet those who have given this a trial have become enthusiastic over 

 the results obtained and consider it a specific. 



It seems hardly possible that a small amount of mercurial ointment 

 applied to a restricted region of a hen's body will free it from lice 

 but the results are above expectation. 



Vice-President G. A. Dean: The paper is now open for discussion. 



Mr. D. M. Rogers: May I ask how frequently the lice must be 

 treated? 



Mr. G. H. Lamson, Jr. : We determined that the application in the 

 summer would last two or three months. When applied in the fall 

 or winter, it would last four or five months, so I believe in the North 

 that three applications would keep hens free from lice throughout the 

 year. Probably in the South it would take four or five more. 



Mr. Z. p. Metcalp: In North Carolina, six applications a year 

 are necessary to keep the hen louse in control. The head louse seems 

 to require more than six applications a year as it is not as easily 

 controlled as the hen louse. 



Vice-President G. A. Dean: We will now pass to the next paper by 

 Mr. Z. P. Metcalf. 



LIME AS AN INSECTICIDE! 



Z. P. Metcalf 



In 1912 Mr. C. B. Williams, chief of the Division of Agronomy of 

 our station called my attention to the ravages of the common and 

 four-spotted cow-pea weevils (Briichus clmiensis Linn, and B. quad- 

 rimaculatus Fabr.) in the cow peas that were being saved for seed by 

 the station. I at once suggested to him that we fumigate them with 

 carbon bisulphide, which was done, using four pounds to 1,000 cubit 

 feet of air space in a very tight bin at 74° F. for 72 hours. Contrary 

 to our expectations, however, the cow pea weevils continued to breed 

 in undiminished numbers, although a great many adults were killed 

 at the time the fumigating was done 



1 Contributions from the Department of Zoology and Entomology of the North 

 Carolina CoUege of Agriculture and Experiment Station, No. 7. 



