202 THE COMMON FLEA. 



in common oil. The dog or cat must be well smeared, and 

 a few hours afterwards is to be washed with soap and water. 

 Abroad a specific is used, and is found indispensable to 

 travellers in the East ; it is the Persian insect powder 

 Pyrethrum roseum which can be bought now-a-days at 

 most of our chemists' shops, in india-rubber balls, from which 

 it can be sprinkled over the skin of any animal. It is 

 essential to attend to cleanliness, and to destroy all fleas or 

 their larvse, wherever dogs are accustomed to sleep, such as 

 in kennels, &c. 



WARBLES OK WORNILS CESTRUS BOVINUS. 



Reaumur, Vallisneri, Numan, Clark, and others, have 

 written descriptions of the gad-fly which attacks cattle in the 

 summer months, and whose larva is enclosed in the swellings 

 of the skin so constantly seen amongst cattle living in the 

 open air. 



Bracy Clark says: "Of all the European species of this 

 genus, this is the largest, and is not unfrequently seen in 

 country situations in the backs of oxen and cows. They 

 form tumours as large as pullets' eggs on the sides, about the 

 back and loins. With us among the country people they are 

 called warbles, wornils, wonnuls, and sometimes bots. 



" When I first took up the investigation of these animals, 

 I was in considerable perplexity what this species could be, 

 since I possessed the CEstrus Bovis of Linnaeus, agreeing 

 perfectly with the description, and which was a horse bot ; 

 nor had I then seen the writings of Vallisneri or Reaumur, 

 which, as Linnsaus had seen and referred to, I did not sup- 

 pose could have fallen into such an error as to have omitted 

 entirely this remarkable species, or have confounded it with 

 the equi; but it so proved; and on obtaining the perfect insect 

 from the back of the cow, the mystery became unravelled; 



