58 DISKASKS OF I'On.TRV. 



consequently, remain by themselves and move about 

 very little. They remain in a recumbent position, 

 resting upon the sternum, are sleep}', and, if forced to 

 run, soon fall from exhaustion. The plumage is dull 

 and rough, the wings are pendant, the eyelids partly 

 closed, the head depressed. The respiration is accel- 

 erated and accompanied by a rattling or snoring sound, 

 particularly during the expiration, and becomes diffi- 

 cult and labored, the bird opening its l>eak from time 

 to time, in order to take a long inspiration. The tem- 

 perature of the body is elevated, the thirst increa?ed 

 and the appetite is diminished or disappears. There 

 is more or less catarrh of the trachea and bronchi, 

 with emaciation and diarrhea leading to death from 

 exhaustion in from one to eight weeks. When the 

 disease is limited to the air -sacs of the interior of the 

 body, emaciation may be the only symptom ; but when 

 it extends to the bones there may be lameness with 

 swollen and painful joints. 



In examining the birds after death, the seat of the 

 disease may be found in the trachea, l)ronchi, lungs, 

 the various air -sacs, and other internal organs. It is 

 sometimes, though rarely, found in the nostrils and in 

 the air -sacs of the interior of the bones. Two kinds 

 of lesions are found. There may be tubercles re- 

 .sembling closelj^ those of tuberculosis. These are 

 whitish or yellowish nodules varying from the size of 

 a pinhead to that of a pea. They may be isolated or 

 joined together in masses of considerable proportions. 

 These tubercles are generally found in the depth of 

 the tissues, and even in the marrow of the bones. On 

 the mucous membrane liningthe air-tubes andair-sacs, 

 the second form of disease process is seen. This con- 

 sists of a membranous formation, an eighth of an inch 



