'M 



«). FA\'i;s. 



In some respects lliis disease i-eseiubles inaiiti:<\ It 

 is, however, produced by an entirely different parasite, 

 and on dose exsnMnation it can be seen that the condi- 

 tion of the skin is different from that whicli exists in 

 mange. The parasite 

 of favns is a vegetable 

 «j:rowth, known as Acho- 



rion schorleinii, 



Favus usually com- 

 mences about the comb, 



head and neck. It causes 



the feathers to become 



brittle and break off and 



fall out, and when these 



are examined clO'sely it 

 is seen that their interior 

 is filled with scales and 



with branching threads 



cesembling minute roots. 



These are the filaments 

 of the vegetable parasite 



or fungus. When the 

 comb is involved, it becomes swollen, its surface be 

 comes scaly, whitish and powderly. The eyelids are 

 frequently afl'eeted, ajid in some rare cases the feath- 

 ered surfaces are involved to such an extent that the 

 bird becomes almost naked. tTpon the skin there de- 

 velops a thick yellowish or grayish crust or scab in the 

 form of rather small, roundish disks, depressed at the 

 centre. Tlie odor of tli<' diseased bird is peculiai- and 



Head and Neck of a Fowl, Affected 

 WITH Generalized Favus. 



