70 
and flea and anthrax, but all his experiments gave negative results, and 
he concludes that ‘infection through the bite of a bed bug either does 
not occur or is exceptional; and further, that infection might occur if this 
bug were crushed, and the part scratched, is self-evident.” And in regard 
to fleas, the anthrax bacilli die off rapidly in them, and the conclusion 
appears justified that they can not play much of a role, if any, in the 
spread of this disease. 
The plague is supposed to be spread in some measure by means of flies 
and other insects. Nuttall’s conclusions, as far as the biting insects are 
concerned, are the same as under anthrax, namely, that infection through 
their bites is exceptional and not the rule, but, ‘ton the other hand, it is 
quite possible that a person crushing an infected bug, and scratching the 
spot where the insect has bitten, may thus inoculate himself with the 
plague bacillus. This, however, would not take place if a sufficient in- 
terval of time had elapsed after the bug had sucked blood containing the 
bacilli.” 
But Nuttall’s experiments with flies infected with the plague bacilli, 
by which he determined that infected flies could live for several days, 
point to the possibility as he rightly concludes, that they play no incon- 
siderable role in the spread of the plague, for they have plenty of oppor- 
tunities to gain access to food into which they might fall and die, or on 
which, in again feeding, they would deposit their excreta laden with 
plague bacilli. 
Nuttall was satisfied that the flies themselves could die of the plague. 
A few experiments are recorded with hog erysipelas, mouse septicaemia, 
recurrent fever, chicken cholera, and yellow fever, which result in very 
positive conclusions. Experimental and other evidence points coneclu- 
sively, however, that Asiatic cholera is disseminated by flies. Tubereulo- 
sis and leprosy are undoubtedly spread in this way. 
Particular attention was called, during the recent war with Spain, to 
the spread of typhoid fever through our camps. In fact, it was well dem- 
onstrated that the fly played a most important part in the spread of dis- 
ease throughout the camps, making due allowance for the other factors, 
such as poor food and bad water. All the conditions about the camps 
seemed to favor the fly in his dirty work. Flies are attracted alike to food 
material and to filth. Fecal matters, fresh from the bowels of typhoid 
patients, and oftentimes without even an apology for disinfection, lay ex- 
