BRONCHOCELE. 23^ 



seldom does any harm. The disease is most common in: 

 limestone districts. 



Treatment. — Applications frequently renewed of unguen turn 

 iodi, or unguentum iodi comp., as follows, potassium iodide 

 5i., iodum 5i., adeps 5iv., are the most successful. The 

 gland may be removed by excision, but the operation should 

 not be resorted to in any but exceptional cases. 



LARYNGISMUS PARALYTICA. 



This condition gives rise to roaring, which may be defined 

 as breathing with a loud and unnatural sound. Properly 

 speaking, roaring in itself is not a disease, but is a symptom 

 of disease. The condition is due in a great majority of cases 

 to paralysis, or atrophy of the dilator muscles of the larynx, 

 the muscles affected being the crico-arytenoideus, posticus^ 

 and lateralis, the arytenoideus, and the thyro-arytenoideus. 



A variety of causes have been assigned for roaring. Mal- 

 formation of any of the air-passages, obstruction of the nasal 

 cavities, occlusion of one of the nostrils, etc., will produce 

 the sound ; but in a pure case of laryngismus paralytica 

 the muscles above-mentioned are paralyzed, or atrophied, in 

 consequence of which the laryngeal opening is not properly 

 dilated, and the air rushing in during inspiration comes in 

 contact with the loosely flapping parts of the larynx, and 

 produces the sound known as roaring. Koaring, from any 

 cause whatever, constitutes an unsoundness. 



Causes. — Any immediate irritation, as laryngitis, etc., by 

 interfering with the nervous supply of the part, has a ten- 

 dency to bring about the disease, by causing degeneration of 

 the muscular fibre. Strangles involving the larynx is also 

 sometimes followed by roaring. In many cases the disease 

 may be traced to an hereditary predisposition on the part of 

 the animal, certain strains of all breeds of horses being 

 peculiarly liable to this disease. Conformation undoubtedly 



