ansmitted to cattle, and
thus with one blow we destroy the entire experimental support which he had
for his argument before the British Congress on Tuberculosis. If, on the
other hand, we accept the conclusion which follows from the principle laid
down by Koch for the discrimination between human and bovine bacilli, and
which appears to be favored by Kossel, we must admit that bovine
tuberculosis is an extremely important factor in the etiology of human
tuberculosis. Of the 39 cases of human tuberculosis tested, 4, or more than
10 per cent, were virulent for cattle and would be classified as of bovine
origin; however, these 4 cases, were all found among the 16 cases of
tuberculosis in children which the commission investigated; hence it is
plain that 25 per cent of the cases tested of tuberculosis in children
would by Koch's method be classified as of bovine origin.

In the Bureau of Animal Industry two distinct lines of experiments have
been carried on, in order that one might serve as a check against the
other. There has been, however, no discrepancy in the results. De
Schweinitz, in the Biochemic Division, Bureau of Animal Industry, isolated
9 cultures from human tuberculosis. Two were derived from human sputum, 3
from cases of generalized tuberculosis in adults, and 4 from cases of
generalized tuberculosis in children. By comparing these cultures with a
newly isolated virulent culture of bovine tuberculosis, there were found
among them 2 cultures from children which were identical in their cultural
and morphological characters with the bovine bacillus. These cultures also
killed rabbits and guinea pigs in as short a time as did the bovine
bacillus. Hogs which were inoculated subcutaneously with these 2 cultures
from children died of generalized tuberculosis. Two calves weighing more
than 300 pounds each were inoculated subcutaneously with these virulent
human cultures, and as a result developed generalized tuberculosis. A
yearling heifer inoculated with 1 of the cultures showed generalized
tuberculosis when killed three months after inoculation. Both the cattle
and the hogs had been tested with tuberculin and found to be free from
tuberculosis before the inoculations were made. It is important to observe
in this connection that 2 out of 4, or 50 per cent, of the cultures
obtained from cases of generalized tuberculosis in children proved virulent
for cattle.

Mohler, working in the Pathological Division, Bureau of An