70 Veterinary Medicine. 



mouth and end iu an early recovery, or it may extend to the 

 organs of the chest and abdomen, or the germs may proliferate 

 largely in the blood and induce fatal results. On the other hand 

 it may become subacute or even chronic, and, as already noted in 

 the case of the parent pigeons, it may persist as an infecting 

 disease without materially injuring the general health of a com- 

 paratively immune animal. 



The affected nasal passages become filled by frothy liquid and 

 blocked by false membranes, so that the bird is driven to breath 

 through the open mouth. The skin around the nares, and eye- 

 lids and the cavity beneath the eye may be covered with the false 

 membrane, by the increase of this product the bones may be 

 driven out of place, so that the palatines press downward, the 

 eyeball is pressed outward and the root of the beak may seem 

 swollen. The false membranes that form on the skin or reach 

 the surface are .soft, creamy, cheesy, or dry, granular and friable. 



When the eye is specially affected there are swelling of the 

 lids, profuse lachrymation, closure of the lids by adhesion, and 

 formation around their borders or on their inner surface and on 

 the membrana nictitans of false membranes which press the lids 

 outward more or less unevenly, and may be easily recognized 

 when the lid i.s everted. The cornea and even the interior of the 

 eye may suffer, leading to perforation, internal ten.sion, and in 

 some cases atrophy, with permanent blindness. 



The tongue may .suffer on the tip as in pip, or on its dorsum, 

 from which the disease extends to the larynx, trachea and even the 

 air sacks, which become filled with false membranes, that are 

 coughed up, and decomposing in the mouth, add to the infection 

 and foetor. Dyspncea and cyanosis of comb and wattles are 

 marked features. 



The extension may take place downward along the alimentary 

 track, the false membranes forming on the gullet or crop and in- 

 terfering with swallowing or dige.stion, or on the intestine and 

 determining a foetid, often greenish or bloody diarrhoea with in- 

 dications of false membranes. Vomiting may be a marked 

 .symptom . . 



The skin is usually attacked secondarily around the margin of 

 the beak, the eyelids, the nares, the ears, the comb, the wattles, 

 the anus, but it may develop at any point where the infecting 

 material has touched an abraded surface. 



