246 Manual of Veterinary Microbiology. 



inoculated is sufficiently large they cause the death 

 of the animal like the tubercles of living bacilli, and 

 with the same general symptoms. Inoculation of a 

 small dose of dead bacilli is followed by temporary 

 loss of condition, and the subject becomes much 

 more sensitive to a later inoculation with virulent 

 bacilli. 



Tuberculosis and scrofula. — The lesions of scrofula 

 are of a tubercular nature; they contain the Koch 

 bacillus. 



M. Arloing has shown that the virus of tuberculo- 

 sis and that of scrofula always infect the guinea pig, 

 whilst the former only is virulent for the rabbit. He 

 has also shown that local tubercular lesions are occa- 

 sioned bv bacilli which have become more or less at- 

 tenuated; sometimes these local lesions are but 

 slightly virulent and are of a scrofulous nature; 

 sometimes they are more active, resembling tubercu- 

 losis properly so called, and like this have a greater 

 tendency to extension. 



M. Arloing is of opinion that the bacillus is attenu- 

 ated in scrofula; M. ISTocard, on the other hand, holds 

 that the diminished activity of the scrofulous virus in 

 the rabbit is due to the feeble receptivity of this 

 species for tuberculosis and to the poverty of this 

 virus in bacilli. 



The virulence of scrofulous products is augmented 

 by their passage through the organism of the guinea 

 pig; whilst tuberculization is slow in the first 

 guinea pig it becomes more and more rapid in the 

 others inoculated later in the same series. 



These observations concerning scrofula of man are 



