RELATION TO OTHER ANIMALS 



161 



Horses and cattle can be very readily freed from 

 lice parasites by a free use of curry-comb and brush, 

 and if occasionally the brush 'be dipped into a pan of 

 crude petroleum so that the tips of the bristles become 

 wet, the coat of the animal will be materially improved, 

 and any louse that is hit will be killed. Kerosene must not 

 be used because that is likely to kill the hair ; but crude 

 petroleum acts as a stimulant and improves its growth. 



There are no animal parasites in the other Neurop- 

 terous orders, and in the great 

 order Coleoptera or beetles there 

 are very few. We have scaven- 

 gers and feeders on dead and de- 

 caying material in great abund- 

 ance, and many beetles live with 

 specific animals in very close re- 

 lationship ; but very few actually 

 occur on the animals themselves. 

 In the United States the mem- 

 bers of the family Platypsyllidce 

 and LeptinidcB are known to live 

 on the beaver and a few other ro- 

 dents that have a dense fur. 



Just what the relation of these parasites is to the host 

 is not entirely clear, but the larvse do not live on it, 

 and feed rather on the waste material in the nests. 



Animal parasites would scarcely be expected among 

 the order Lepidoptera, or butterflies and moths, and 

 strictly speaking there are none. Yet it is certain that 

 some of the small moths belonging to the Tineids, 

 which include our "clothes moths," do actually breed 

 and develop in the fur or wool of animals like the sloth, 

 certain sheep, etc. There is such a thing, then, as a 

 fur or pelt becoming moth-eaten, even while it still 

 covers the body of its owner, 

 ii 



FIG. 68. Platypsylla cas- 

 toris: parasite on beaver. After 

 Westwood. 



