76 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 134 
leprae-like, acid-fast bacilli in their guts. Of 105 cockroaches caught 
in the slight-case wards, 12.3 percent carried this bacillus. 
Cockroaches, Venezuela (Tejera, 1926): Acid-resistant bacteria 
similar to M. leprae were found in cockroaches captured in leprosy 
colony at Cabo Blanco, but this bacterium was never encountered in 
cockroaches captured elsewhere. Belgian Congo (Radna, 1939): 
Three of eight cockroaches captured in the hut of a leprosy patient 
were found to excrete M. leprae in their feces over a period of 10 
days after capture. 
Experimental vectors—Blatia orientalis, Europe (Paldrock im 
Klingmiiller, 1930): After 14 days, leprous bacilli were still abundant 
in the feces. Nyasaland (Lamborn, 1940): In one experiment, 38 
cockroaches were fed for 9 days on a crust removed 6 months earlier 
from the ear of a leprous patient. Feces, passed immediately after 
this food was removed, contained large clusters of short filamentous 
bacilli, presumably the leprous organism. Ten additional cockroaches 
were allowed to feed on a dressing just removed from a leprous sore. 
M. leprae was definitely found in feces passed on the third day after 
removal of this food. Acid-fast particles were recovered on the fifth, 
eighth, twelfth, fourteenth, and twenty-first days. 
Blattella germanica, Europe (Paldrock in Klingmiller, 1930) : The 
cockroaches still excreted the bacilli in the feces 14 days after feeding 
on leprous nodules. Southern Rhodesia and Kenya (Moiser, 1945, 
1946, 1946a, 1947; Anonymous, 1946): Cockroaches were fed corn 
meal inoculated with material from ulcerating nodules containing M. 
leprae. These bacilli were recovered in large numbers from the guts 
(up to the nineteenth day after feeding) and from dried feces of the 
insects. The bacilli remained morphologically unchanged in dried 
feces for several months. The bacilli were found in the feces of a 
series of five cockroaches, each fed the powdered dry feces of its 
predecessor. 
Nauphoeta cinerea, Nyasaland (Lamborn, 1940): Thirty-four 
newly born cockroaches fed for 3 days on a dressing removed from a 
leprous sore. Globi were found in abundance in feces passed on the 
third day. Acid-fast organisms were recovered at intervals over a 
period of 66 days. Similar results were obtained with 10 other cock- 
roaches. Feces of a control series of cockroaches remained free of 
acid-fast organisms. 
Periplaneta americana, Gold Coast Colony (Macfie, 1922): The 
insects were fed scrapings from the nose of a leper. M. leprae ap- 
peared in the feces for 2 days after the meal. The organism appeared 
to pass unharmed through the intestine of the cockroach. 
