PRESIDENTIAL ADDRESS. 4] 
the recent infested wheat areas, the only fleas encountered 
(all from one sample—they were not looked for in others) 
were the blind flea Ctenopsylla muscult, which does not, 
apparently, bite man. 
The two common species of rat are therefore the chief, in 
Australia, perhaps, the only, means available for the distri- 
bution of the plague bacillus apart from direct infection 
from man to man in pneumonic plague. A town free from 
rats will be free from a visitation of ordinary plague; a 
town that reduces its rats to numbers so small that a plague 
epizootic cannot establish itself amongst them, if plague 
rats are introduced, will be free; a town that lets its rats 
multiply is exposed to a menace that may lead to enormous 
financial losses and possibly a heavy death roll. It is, of 
course, an exceedingly difficult task to keep down the rat 
population. In spite of all efforts, they may still be pre- 
sent in large numbers. When plague has never reached 
such a town, or its ravages and cost have passed into ob- 
livion, the constant warfare against rats may wane and the 
authorities cry out at a seemingly needless expense. Days 
of financial stringency may arise, and the pruning knife lop 
off more and more of this important public protection. It is 
the old story again of one of Britain’s little wars. The 
expedition had been a success; the native tribes had made 
suitable submission; the general in command was submit- 
ting his report on the part played by the various units im 
achieving such desirable results. For the medical work, he 
wrote, little praise could be bestowed, because, as a matter 
of fact, the staff had had nothing to do, there had been no 
sickness at all—but in truth there had been no sickness 
because of the very efficiency of that staff 1n preventing its 
appearance. Had typhoid fever decimated the ranks and 
slain more than the enemy, had dysentery incapacitated the 
troops, the medical staff could have done tangible work in 
