RESPIRATORY APPARATUS. 103 



A catarrh involving but one side of the soft palate or pharynx 

 may also show a discharge from only one nostril. 



Of especial importance is the varmtion in quantity of the 

 discharge. In some cases a copious amount of discharge is 

 ejected when the head is suddenly lowered [unreining after a 

 drive], while for a day or more there is present either no dis- 

 charge at all or only. a very slight one. This symptom is 

 characteristic of catarrhs of the frontal and superiormaxii- 

 lary sinuses and of the guttural pouches. 



b. The color. The color of the nasal discharge de- 

 pends upon the character of the inflammation, and also the 

 presence of foreign mixtures. It will vary from colorless to 

 grey, zi'kite, yellow, red, brown or green in all their different 

 tints. During the course of a disease the color of the nasal 

 discharge will change with the character of the inflamma- 

 tion. A serous or mucous discharge is usually colorless; a 

 purulent discharge is grey or yellow or may be of a greenish 

 hue. 



A green discharge is usually due to an admixture of the 

 chlorophyll of the food, deglutition being difficult. Food 

 particles are always present in such cases. In rare instances 

 a greenish tinge is seen, due to decomposed blood coloring 

 matter being present in the discharge. 



A yellozv, rust-colored ["prune juice"] discharge is seen 

 m hemorrhagic hepatization of the lungs (contagious pleuro- 

 pneumonia of the horse). It is due to an admixture of blood 

 coloring matter. 



In rare instances a rusty brown nasal discharge is pres- 

 ent m severe catarrhal afifections of the anterior respiratory 

 passages (strangles, pharyngitis). 



A^ bloody discharge {cpistaxis) is observed onlv when 

 blood in toto is present. It may be due to: 



1. Finger-nail injuries to the mucous membrane of the 

 nose or fractures of nasal bones. In the dog the presence 

 of pentastomum tenioidcs may lead to bloody nasal discharge, 

 and in sheep the larvae of oestrus ovis. 



