THE HEAD-LOUSE 73 



by scalp troubles, such as eczema, so often started 

 by the effects of vermin. A second precaution 

 that is useful is the use of pomades and oils for 

 the hair. All lice hate grease, which runs over 

 their bodies and chokes them. It is not necessary 

 that any medicament should be added to the 

 grease, and some of the so-called louse-destroying 

 pomades are poisonous and dangerous in use. 



Many primitive tribes have a habit of greasing 

 heavily both their heads and bodies when fat 

 or oil is available. In Africa, in most native 

 gardens quantities of the castor-oil plant may be 

 seen growing, and apparently the oil produced 

 is used for no other purpose. The author has 

 also seen them, when a hippopotamus has been 

 killed, cut lumps of fat out of the animal and 

 smear themselves from head to foot. Whether 

 these precautions owe their origin to their bene- 

 ficial results in regard to lice, it is hard to say, 

 but at any rate the benefit accruing to them in 

 this respect is very real. 



Mechanical means are more effective for head- 

 lice confined to the head than for the body-lice ; 

 but even with these patience is necessary, and it 

 can hardly be expected that an established 

 colony of them can be all removed by the comb 

 at a single operation, as there is a limit to the 

 patience of the sufferer if not to that of the 

 operator. The comb used should have fine 

 teeth, and a little while before the combing the 

 hair and scalp should be thoroughly washed 



