460 
PATHOLOGICAL PHYSIOLOGY. 
Third .—The most important difference rests upon the propa¬ 
gation of the infection. In the guinea-pig, the virus is propa¬ 
gated by the way of the lymphatics, with perfect regularity. If 
an animal is inoculated on the internal face of the thigh, the cor¬ 
responding inguinal glands become enlarged and hard, from the 
10th to the 15th day—seldom later; the sub-lumbar glands of 
the same size become tumefied, the spleen becomes tuberculous ; 
then the retro-hepatic gland, then the lungs and the bronchial 
glands. The infection remains unilateral as far as the diaphrag¬ 
matic region, then somewhat indefinitely spreads itself to the right 
and to the left. In two months the infection is complete. When 
the inoculation is made at the base of the ear, the virus progresses 
toward the chest, successively affecting the lymphatic glands 
located on its way. Consequently there is, so to speak, not one 
guinea-pig inoculated under the skin that does not present a 
glandular tuberculosis. 
In the rabbit, on the contrary, complete glandular tuberculosis 
has never been observed after inoculation with human tubercu¬ 
losis. The local lesions are often either absent, or they only 
consist in small spots of granulations, or a caseous abscess; the 
visceral lesions are pulmonary or pleural; but, between the inocu¬ 
lated thigh aud these organs, there is not the slightest lymphatic 
swelling. In two cases, however, where the local alterations had 
been accompanied with large abscesses, we have observed hyper¬ 
trophy of the glands; but inoculation proves this not to be 
specific. 
To resume: In the rabbit there is visceral tuberculization 
without glandular lesions; in the guinea-pig there are unmistak¬ 
able marks of the passage of the virus through the lymphatic 
system. 
Fourth .—We have sought for the cause of this difference, 
querying whether it did not reside in the physical condition of 
the infecting matter. With this in view, we made subcutaneous 
injections with sifted and filtered virus, and inoculated with the 
lancette of coarsely-marked tuberculous masses. The number of 
tuberculizations was smaller in the second case, but in the propa¬ 
gation of the disease its mode was always the same. The differ- 
