06 DADD'S VETERINARY MEDICINE AND SURUERY, 
and from thence extends to the trachea; but there are, we suspect, 
very few cases indeed, if any, ia which the disease is confined ta 
the trachea. In cases of croup that have terminated rapidly in 
death, the inflammation and pseudo-membranous exudation which 
form so striking a feature in this disease are found only in the 
larynx and upper portion of the trachea. When death occurs at 
a later period, the exudation is often present in the trachea along, 
or in the trachea and bronchi. It is never found to exist in the 
latter tubes alone. It has been attempted to be shown, by JURIN 
and others, that in the ordinary form of croup the disease is, in its 
first stages at least, simply a tracheitis, and that in the more vio- 
lent and rapid form (suffocating croup) the inflammation is con- 
fined tothe larynx. Although this is not strictly true, as is proved 
by the result of numerous dissections, yet our observations have 
shown us that in cases marked by symptoms of great violence, 
which are sudden in their onset and rapid in their progress, the 
indications of inflammation are to a much greater extent, and the 
pseudo-membranous exudation more copious about the larynx, glot 
tis, and upper portion of the trachea, than in cases in which the 
disease succeeds to bronchitis, runs a more protracted course, and 
is attended by symptoms of less violence. 
The disease generally makes its appearance during the latter 
part of winter and in early spring, and most frequently occurs 
among horses just introduced to city life. The subjects such as 
the author has had occasion to treat were young, most of them of 
the lymphatic temperament, having short, thick necks, which 
abounded in a profuse development of adipose and cellular tissues, 
which results in a rotund bodily conformation. This, perhaps, 
goes to show that some hereditary idiosyncrasy plays a part in the 
creation of the disease. 
Causes.—The indirect causes of the disorder are embraced among 
the evils of domestication, which include errors in diet, impure 
air, and bad management. It usually dates its origin from what 
are generally considered as the causes of common cold. Several 
days previous to the attack, the animal appears “ dumpish,” drowsy, 
and inactive, having little desire for artificial food, and less for 
water. The eyes appear somewhat tumefied, and the respirations 
are laborious, having a pecuuar, croupy sound, accompanied by a 
distressing cough. Tlie respirations can be heard at a distance (as 
the disease progresses), and on making pressure in the region of 
