10 ANIMAL PARASITES 



When the eggs are laid, they stick firmly to the 

 human hair, and are called nits. This we will 

 more particularly explain further on. In six 

 days the young escape from the Q^g^, and are 

 ready to lay eggs at the age of eighteen days. A 

 female lays some fifty eggs in all. We thus see 

 why such enormous quantities of the animals are 

 often seen, and how they propagate with such 

 astonishing rapidity. 



It is easy enough to tell when a person is in- 

 fested with these vermin, because the animals 

 creep about upon the head, and their eggs are 

 large enough to betray themselves to thd" naked 

 eye, especially on dark hair. As the insect can 

 run about, the eggs will be found strung along the 

 whole length of the hair. 



We said this kind inhabits only the scalp, where, 

 by their creeping about, but more especially by 

 their biting the skin, in pursuit of nourishment, 

 they cause intense and constant itching, and hence 

 intense and constant scratching on the part of the 

 person infested. We all know how tender the 

 scalp is made by hard brushing, combing, or vio- 

 lent shampooing, and can therefore readily under- 

 stand that the constant digging the finger-nails 



