WEST OF SCOTLAND VETERINARY MEDICAL ASSOCIATION. 073 
( c ) Encysted, or enclosed in a cyst or lymph sac; frequently 
seen in the interior of the liver and lungs. 
One only of these forms may exist in an animal, or it may be 
the subject of all, and even one organ may have within its struc¬ 
ture encysted tubercles; underneath the coats of its large vessels 
infiltrated, and externally granular. 
Tubercle gives rise to several distinct, nosologically arranged 
diseases, and, like the different kinds of tubercle, one only of 
these diseases may exist, or several together, or one may be, and 
frequently is the natural sequence of the other. Thus we are in 
the habit of speaking of tabes mesenterica, phthisis, tubercular 
meningitis, tubercular arthritis, tubercular hepatitis, or what, in 
my estimation, would be better, hepar tuberculosis, tubercular 
ostitis, and tuberculous glands. 
Tubercle is frequently confounded with other morbid products, 
particularly cancer, and the changes brought about by parasites; 
but can be distinguished from either by careful examination. 
Some authorities deny the possibility of cancer and tubercle co¬ 
existing ; others hold that such may occur, and cite cases—Lebert 
and Martin, of Munich [Lancet, August 16th, 1845). That tubercle 
and parasites are frequently present in the same animal is an 
acknowledged fact, a good example of this kind, in the horse, 
will be found recorded by myself in the Veterinarian for 
January, 1864. 
Characters of Tubercular Formations .—These vary according 
to the structure invaded and the age of the deposit. 
In the first stage, it is lymphoid in character, as demonstrated 
by Paget; afterwards it assumes several forms, as the gray or 
solid, being of a solid compact structure, and when cut into 
resembling tough cheese, or wax; and the yellow, or soft, being 
more loose in structure and of a curdy appearance or consistence. 
In its degeneration we have cornification and ossification of gray— 
and it is this which is likely to be confounded with the structural 
alterations produced by parasites, fatty degeneration, suppura¬ 
tion, and cretafecation of yellow. Cretafecation likewise being 
confounded with parasitical productions, and in conjunction with 
cornification and ossification, thought to be due to an effort on 
the part of nature to imprison the tubercular matter, and thus 
prevent it working further harm to the system. Albuminous and 
fatty degeneration are often found associated, and all of the 
degenerative processes may be going on in one organ simul¬ 
taneously. 
The albuminious degeneration is seen most frequently in the 
laryngeal lymphatic glands of young animals, especially cattle, 
and when the sac is opened it escapes as a yellowish, cohesive 
mass, resembling coagulated synovia, only more opaque. 
