422 



ZOOLOGY 



spin webs under leaves, in which whole colonies of the mites 

 dwell. 



The IxoDlDAE or ticks are blood-sucking mites which live 

 on undergrowth in forests ; the females crawl upon man, 



i Fig. 243, — The same {Ixodes aegyptms) ; under side. 



a. Chelicerae. e,f. Maxillae and labium soldered 

 i, Pedipalpl. together, 



c. Genital aperture. g. Sternum. 



d. Anal aperture. 1-7. Joints of leg. 



cattle, or even snakes, and attach themselves by their strong 

 rostrum. They suck blood to such an extent that their bodies 

 sometimes swell to the size of a small walnut. 



The Tyeoglyphidae include Tyroglyphus siro, the cheese 

 or flour mite, and several other species which feed on vegetable 

 substances. 



