548 
W. E. A. WYMAN. 
transparent fluid, usually one in a cyst, but sometimes two or 
three and even five or six. The cyst and contents including 
the worm are subject to both fatty and calcareous degeneration ; 
in the latter form of degeneration the trichinae are often black 
and fragile, being frequently broken into fragments in the 
preparation for examination. Trichinized flesh does not differ 
from the non-infested flesh in appearance and is harmful as food 
only when eaten uncooked. The communities and nations 
which eat their pork raw naturally require the inspection and 
condemnation of trichinized pork. 
This presentation in short review of the gross diagnostic 
lesions of diseases and conditions of food animals, and com¬ 
ments as to the disposition of the flesh is all too brief, but may 
serve to open the discussion. Diseases and conditions which 
have not come under the writer’s personal observation have 
been purposely omitted. 
IMPORTANCE OF COUGH IN A CLINICAL SENSE. 
By W. E. a. Wyman, V. S., Clemson Coeeege, S. C. 
Presented as a Thesis to the F'aculty of the McKillip Veterinary College, Chicago, 
April, 1898. 
PJiysiological Consideratioiis. —By cough is understood a sud¬ 
den reflectory act depending on the irritation of the cough centre 
in the medulla oblongata. Cough is one of the most important 
factors in physiological expectoration^ being an involuntary act 
in the horse. Cough therefore is a symptom, the result of a 
stimulation of its centre in the medulla, which may be of cen¬ 
tral or peripheral origin. Any stimulation of the cough centre 
calls forth a centrifugal stimulation of the htferior laryngeal 
nerve —the motor nerve of the larynx—and a clonic spasm of 
the glottis results ; at the same time centrifugal stimulation of 
the motor nerves of the auxiliary muscles of respiration follows. 
This results in a sudden high tension of the column of air below'^ 
the glottis, which overcomes the musciflar opposition of the laryn* 
geal muscles and that peculiar act—termed cough—bursts forth. 
