CHAPTER XVIII. 



T'uberculosis — Microscopic appearance of miliary tubercles — Encap- 

 sulation of tuberculous foci — Diffuse caseation — Cavity-formation 

 — Primary infection — Modes of iufection — Location of tbe bacilli 

 in the tissues — Staining-peculiarities — Organisms with which 

 bacillus t'uberculosis may be confounded: bacillus leprx; bacUlus 

 syphilidis; bacillus smegmatis — Points of diiferentiation — Acid- 

 proof bacilli — Pathogenic streptothrices — Streptothriz actinomyces — 

 Streptothrix madurse — Strcptotlirix farcinica — Streptothrix Eppingeri 

 — Streptothrix pseudotuberculosa — Bacillus of influenza. 



C. LOCAL OR GENERAL TUBERCULOSIS. 



Should the animal succumb to neither of the septic 

 processes just described, then its death from tuberculosis 

 may be reasonably expected. 



When this disease is in progress alterations in the 

 lymphatic glands nearest the site of inoculation may 

 be detected by the touch in from two to four weeks. 

 They will then be found enlarged. Though not con- 

 stant, tumefaction and subsequent ulceration at the 

 point of inoculation may be observed. Progressive 

 emaciation, loss of appetite, and difficulty in respiration 

 point to the existence of the general ttiberculous process. 

 Death ensues in from four to eight weeks after inocula- 

 tion. At autopsy either general or local tuberculosis 

 may be found. The expressions of tuberculosis are so 

 manifold and in different animals vary so widely the 

 one from the other, that no fixed law as to what will 

 appear at autopsy can d priori be laid down. 



The guinea-pig, which is best suited for this experi- 

 ment because its susceptibility to tuberculosis is greater 

 and more constant than that of other animals usually 



330 



