that only eiables ihem lo bite. They live ou the 

 crusts, scales and dead cells that gather on the surface 

 of the skin and that are prevented from falling off by 

 the feathiers. 



There are several varieties of lice belonging to foui 

 principal genera: those are Goniodes, Goniocotes, Lip 

 eurus and Menopen. While these parasites differ con 

 siderably as regards their shape and size they reseni 

 ble each other very closely in their habits. All of 

 them are very small insects, from 1-100 to 1 « incl 

 long and their bodies are plainly divided into three 

 parts; the head is very large and flat, the thorax, or 

 second segment, is roundish and considerably smaller 

 than the head ; the abdomen, or 

 most posterior segincnt, is ]on2, 

 oval and plump. Their color 

 is usually grayi.sh or yellowish, 

 but some of tliem show differ- 

 ent shades of brown. Although y^^fMi; Jltf;*\, 

 these parasites do not pene- ^'^^~-*^^\* 

 trate the skin and suck the ^ -^ " '^'^ '» 

 blood as fleas do, and as the 

 lice of mammals do, they cause 

 a great deal of itching and an- 

 noyance while crawling about 

 over the surface and sometimes 

 they bite the .skin and in that 

 way occasion much irritation 



At one time it was thought that lice were bred by 

 filth and that they generated themselves, as it were, 

 in dirty places, but it has been shown that this is not 

 the case and that they are only produced by like para- 

 sites and have the property of reproducing themselves 



Chicken Louse. 



Gonioiks clmimiUs, male. 



One of the mo8t common vt 



rieties. 20 times natural size. 



