PARASITOLOGY. 33 



solution of creolin. Creolin may prove fatal to cats. 

 Tobacco dust or pyrethrum may be dusted in infested 

 quarters. 



PuLEX Avium (Avis — bird). 



Synonym. — Bird flea. 



History. — Found in central and western United 

 States. 



Description. — The head is rounded, and is not pro- 

 vided with spines on the lower border, but a row of 

 minute bristles is found on the side. The mandibles 

 are short. 



Animals Infested. — The attack is made principally 

 upon small birds. 



THE LICE. 



Phthiriasis (Lousiness) — (Louse). 



Phthiriasis is the condition of an animal or bird 

 infested with lice. The lice infesting the domestic 

 animals are divided into three families, viz.: Pedicu^ 

 lidae, Philopteridae and Liotheidae. 



Under the first is placed the genus Hematopinus. 

 Under the second is placed the genus Trichodectes. 



Those species of lice belonging to the genus Hem- 

 atopinus are provided with a piercing apparatus 

 which projects anteriorly from the head. They live 

 upon the blood of the host. 



Those species belonging to the genus TrichodeC' 

 tes are provided with mouth parts arranged on the 

 under part of the head. They live by mastication 

 from epidermis and hair of the host. 



The lice are oviparous ; the eggs are called nits 

 and are cemented to the hair. The eggs are oval in 

 shape and white in color. 



Sympioyns. — Infested horses and cattle are noted 

 to rub against fences and posts, corners of buildings, 



