54 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 134 
Experimental vectors.—Blatta orientalis, Italy (Cao, 1898 ; Spinelli 
and Reitano, 1932): After experimental feedings, the cholera vibrios 
passed unharmed through the digestive tract of the insect. Cholera 
vibrios survived in the insects’ intestinal tracts for 15 days and were 
found in their feces 86 hours after being ingested (Spinelli and 
Reitano, 1932). 
Blattella germanica, Orient (Toda, 1923): 94 cockroaches (col- 
lected from Japanese ocean liners) were fed V. comma in bread. The 
organism was recovered from 15 percent of the insects, from feces 
or from the intestines after death. The feces contained viable vibrios 
up to 3 days after the infective meal. Germany (Jettmar, 1927): 
Cockroaches fed cholera organisms showed a higher mortality than 
those fed plague bacilli. 
Periplaneta americana, Philippine Islands (Barber, 1914): Feces 
containing vibrios were obtained from 8 cockroaches 6 hours after an 
experimental feeding with feces from a cholera patient. The organism 
appeared in enormous numbers in the feces for at least 2 days there- 
after and in smaller numbers 79 hours after ingestion. There was no 
loss of virulence for guinea pigs after the vibrios had been in the in- 
sects’ intestines 29 hours. Regurgitated food contained vibrios. 
Cholera vibrios in cockroach feces will survive on human food for at 
least 16 hours after discharge from the insect. Netherlands (Akker- 
man, 1933): In 12.7 percent of the cockroaches there were vibrios 
in the feces 24 hours after feeding. One insect excreted vibrios in its 
feces 3 days after feeding. Formosa (Morischita and Tsuchimochi, 
1926) : 25 insects were fed on a culture of cholera vibrios. Intestinal 
contents of groups of 5 were positive 3.5 and 12 hours after feeding. 
After 24 hours, 3 of 5 were positive; after 48 hours, 2 of 5 were 
positive ; after 68 hours, all were negative. Fecal examinations of 10 
cockroaches were positive 5 to 34 hours after feeding; feces excreted 
after 48 to 53 hours were partly positive; after 57 hours all feces were 
negative except I positive at 67 hours. The average ratio of positive 
feces was 16.3 percent. Intestines were negative for V. comma after 
68 or 70 hours. 
Periplaneta australasiae, Formosa (Morischita and Tsuchimochi, 
1926) : One specimen that was fed . comma excreted feces positive 
for the organism. 
Vibrio metschnikovii Gamaléia 
Synonymy.—“Vibrione di Metschnikow” of Cao. 
Disease —Choleralike disease of chickens, pigeons, and other 
animals. 
