The True Lice 



agreeable parasites, to do some good original work. The old 

 Dutch naturalist, Leeuwenhoek, once started an experimental in- 

 vestigation of Pediculus vestimenti, using his own person as the 

 breeding ground, but, beyond the conclusion that the species is 

 very prolific, he reached no results of particular value. Mercurial 

 ointment is a sovereign remedy for the species which attack 

 human beings, while different oily mixtures are used with success 

 on domestic animals. 



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