PARASITOLOGY. 41 



whose quarters are separated only by a partition, 

 may get upon horses and cattle and cause temporary 

 parasitism. Each parasite has its own host or hosts 

 and will not live permanently upon another. 

 Lice of Birds. 



The Large Hen Louse. — Menopon Biseriatum. 

 This is the largest louse found upon the hen. It 

 is about one-twelfth of an inch in length, light in 

 color, with mouth parts arranged for mastication as 

 illustrated in Fig. 10. The free extremities of the legs 

 are provided with booklets which aid in holding on. 



The smaller variety of this genus, Menopon 

 Pallidum, also has been studied, but is far less 

 common in the United States. This louse is found on 

 young and old chickens. 



CO V 



q: - 



Figr. 10. — Menopon biseriatum (from a hen), greatly enlarged; a, 

 head, which is provided with mouth parts; b, thorax provided with 

 three pairs of legs; c, abdomen. 



The Turkey Louse. — Goniodes Stylifer. This 

 louse is found on turkeys and is thicker than the 

 one just described. Like it, the mouth parts are 

 arranged for mastication. It is illustrated in Fig. IL 



LiPEURUS /nfuscatus. This is another louse that 

 may infest chickens. A study of Fig. 13, shows its 

 mouth parts and legs similar to the other lice. Its 

 general shape is different. It is not so common as the 

 large hen louse. 



