184 
DISEASES OE THE LARYNX AND TRACHEA. 
Lee removed a cartilaginous growth from the vocal cord of a horse which 
had suffered from broken wind and was unable to neigh ; recovery was complete 
in six weeks. Besnard lost a six year old mare by suffocation produced by 
a pedunculated cystic polypus, as large as a walnut, which had its seat at the 
base of the epiglottis, and caused difficulty in swallowing, together with severe 
dyspnoea and attacks of coughing. Degive believed that apnoea arose from the 
epiglottis being pushed into the larynx by the swelling during deglutition, and 
not by the latter being swallowed, as Besnard thought. Lehnhard found a 
retention cyst, as large as a hen’s egg and full of clear fluid, on the anterior 
surface of the epiglottis in a horse which had suddenly died from suffocation. 
Tuberculosis of the larynx is common in oxen. Confusion with 
actinomycosis tumours often occurs, but a case of tuberculous new 
growth in the larynx of an ox w 7 as described by Johne, who had already 
drawn attention to the similarity of the two diseases. Prietsch and 
others noted tuberculosis of the larynx in cows on post-mortem. 
Cadiot and Dollar (p. 100 of “ Clinical Veterinary Medicine and Sur- 
gery”) describe a number of cases of tuberculous ulcer in the neck in the 
dog and cat. The pathogeny of the condition is as follows:—In animals 
with tuberculous lesions of the lung coughing is common, and virulent 
tuberculous material is continually being passed into the pharynx, the 
mucous membrane of which becomes inoculated (auto-inoculation). The 
disease soon extends to the neighbouring lymphatic glands, which, under 
the pressure of the collar, become inflamed. Suppuration of the sur¬ 
rounding tissues and ulceration of the skin follow. The w^ound thus 
produced rarely heals, and in most of the cases death occurs within a few 
weeks or months from generalised tuberculosis. 
Symptoms and progress. The first stages in the development of new 
growths are naturally beyond the field of clinical observation. Dyspnoea 
and, under certain circumstances, disturbance in swallowing are only 
produced after they have.reached a certain size. On the epiglottis, how¬ 
ever, they may attain considerable dimensions before marked symptoms 
appear ; but difficulty both of breathing and swallowing are then noted. 
As in diseases of the tongue, and in the so-called pharyngeal lymphoma, 
dyspnoea may occur, particularly during feeding. The disturbed respira¬ 
tion and deglutition are not uniform in their appearance, as Thicker and 
Dieck have noted in horses. Pedunculated tumours on the base of the 
tongue, dropping on to the larynx, suddenly produce symptoms of severe 
inspiratory dyspnoea, from which the animals sometimes fall and occa¬ 
sionally die of asphyxia. The sudden appearance of dyspnoea, without 
febrile or other constitutional disturbance, denotes the presence of such 
tumours. I he condition may be easily mistaken for cramp or oedema of 
the glottis. 
The exterior of the larynx is seldom visibly altered. Only where the 
new growth has spread to the exterior, or has produced marked changes 
in the wall of the trachea, does the region of the larynx appear fuller 
