522 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Tuberculosis and Leprosy.* — Dr. B. Rake records some experiments 
which seem to settle the long disputed question whether certain patho- 
logical lesions and morbid products found in cases of leprosy are tuber- 
culous or leprous. Guinea-pigs were inoculated with pulmonary tubercles 
from three cases of mixed leprosy. The usual appearances of guinea-pig 
tuberculosis were found. Cover-glass preparations showed bacilli indis- 
tinguishable from tubercle bacilli. Cultivations in glycerin-agar failed. 
As attempts to inoculate guinea-pigs with leprosy have always 
failed, it seems justifiable to conclude that the guinea-pigs became 
tuberculous from the infection derived from the pulmonary tubercles of 
the lepers. 
The author points out that the present position as to the relation of 
leprosy to tuberculosis is as follows : — Inoculation experiments have 
shown that the visceral nodules in lepers are tuberculous and not 
leprous. It is quite possible that leprosy and tuberculosis may be 
caused by the same bacillus, but this has not yet been proved. 
Morphology and Biology of the Tubercle Bacillus. | — According 
to Dr. F. Fischel the exciting cause of tuberculosis is a pleomorphous 
and variable micro-organism. The author bases his proposition partly 
on the observations of Metschnikoff and Mafucci, and partly on his own. 
He succeeded in demonstrating in the marginal zones of tubercle 
cultivations on agar and serum at 40°, long filaments, which were 
usually vertical, though occasionally short branches going off at an 
acute angle were observed. Occasionally forked and felt-like appearances 
were observed. In some cultivations of fowl-tubercle the author found 
drumstick-like forms, the pyriform expansions of which contained 
small, bright, round or oval forms, somewhat resembling anthrax spores, 
and these possibly are the representatives of gonidia. 
The form of the bacillus was found to be considerably influenced by 
the composition of the cultivation medium, e. g. blood-serum, agar, &c., 
containing different amounts of pepton, and charged with boric acid and 
thymol. 
Bacillus of Influenza.^ — Dr. L. Letzerich has constantly found in 
the blood of influenza patients very small free bacilli, which stained 
with hot methyl-violet, showing a tendency to red with darkly stained 
ends. Only potato cultivations succeeded. The author convinced 
himself that these bacilli were identical with those described by Pfeiffer 
and Canon. The number of bacilli found in the blood at the beginning 
of the disease is very great, but they gradually diminish as the disease 
passes away, and at the same time always stain more faintly. 
Bacterium pyogenes and B. coli commune.§ — Dr. Th. Reblaud, in 
the course of examinations of a case of cystitis, was struck with the 
resemblance exhibited by the micro-organisms so frequently found in 
infected urine, and so carefully studied by Clado, Halle, and Albarran, 
* Lancet, i. (1893) pp. 719-20. 
f Fortschr. d. Med., x. No. 22. See Centralbl. f. Bakteriol. u. Parasitenk., xiii. 
(1893) pp. 124-5. 
X Zeitschr. f. Klin. Med., xx. No. 3. See Centralbl. f. Bakteriol. u. Parasitenk., 
xiii. (1893) pp. 284-5. 
§ Bull. Med., 1891, p. 1180. See Centralbl. f. Bakteriol. u. Parasitenk., xiii. 
(1893) p. 285. 
