PARASITIC INSECTS 



in camps or prisons. The irritations they produce cause what is- 

 known as Pediculosis or Phthiriasis, after the scientific name of 

 the insect. Lice may move from one person to another, so that 

 cleanliness will not always prevent their appearance. The 



FIG. 34. Four different kinds of lice. 



A, chicken louse; B, head louse; C, crab louse; D, body louse. (After 



Piaget and Denny.) 



best remedies for the head louse are a fine-tooth comb and a 

 thorough greasing of the hair, which chokes the lice. The body 

 lice which infest clothing may be killed by boiling the garments 

 in water, baking them, or dipping in gasoline. Wherever irrita- 

 tions of the skin occur, an application of a mercurial ointment or 



