pearaucL' of a bare S]jot about the ueck or ou the head. 

 The feathers become dry and brittle and either break 

 off or fall out. Then the skin becomes cjovered with 

 yellowisli scales which gradually increase in thickness 

 aa tlie disease advances until Ihey sometimes reach a 

 thickness of an eishtli of an inch. Wln-n old, these 



scales are grayish and have the ap])earaiice of thick 

 scabs. If they are pulled off it is found that the skin 

 beneath is re^d and bleeds easily. As a rule these 

 areas do not itcii, but sometimes they do, and then the 

 bird scratches them vi^oronsly. After becoming es- 

 tablished about the head and neck the disease may 

 spread to the body and sometimes covers a very large 

 surface. The sj-roptoms of this affection resemble 

 those of favus so closely that it has been thought by 



