XIV] BACILLUS TUBERCULOSIS 351 



Scrofula and Lupus 



Koch and many other observers have shown that, both in 

 scrofula and lupus, tubercle bacilli occur, and that with both 

 these materials general tuberculosis can be induced in 

 guinea-pigs. But since these two diseases are in the human 

 subject well-marked disorders, distinct from pulmonary 

 tuberculosis, it is necessary to assume that the tubercle 

 bacilli in the three diseases possess some functional differ- 

 ences. To say that lupus is a form of tuberculosis of the 

 skin does not cover the facts, since real tuberculosis of the 

 skin does occur, and is totally different from lupus ; so also 

 scrofula is riot merely tuberculosis localised in the cervical 

 lymph glands, since, in many instances, it does not lead to 

 pulmonary and general tuberculosis, whereas the true tuber- 

 culosis of lymph glands does do so. It is quite feasible to 

 assume that both lupus and scrofula are tuberculosis, but 

 that in origin and virulence their tubercle bacilli are different 

 from the bacilli, causing true tuberculosis. That the virulence 

 of the virus of lupus and scrofula cannot be the same as 

 that of the material of human and bovine pulmonary 

 tubercle is proved by experiments of Dr. A. Lingard,i who 

 showed that the duration and extent of the disease induced 

 by inoculation of lupus or scrofula into guinea-pigs are quite 

 different from that induced by pulmonary tubercular matter, 

 and, further, that if a guinea-pig is made tubercular with 

 scrofulous matter, and the tubercle of such an animal is 

 again transmitted by inoculation through several generations 

 of fresh guinea-pigs, the disease thus produced gains 

 gradually in shortness of duration and intensity, until after 



^ Reports of the Medical Officer of the Local Government Board, 

 1888-89, p, 462. 



