days
after they have sucked the blood of an animal dying with plague. In
bugs, not previously starved or starved only for a short time (one
to seven days), the plague microbes disappear on the third day; in
those that have been starved for four to four and one-half months,
after eight or nine days.

"(5) The numbers of plague microbes in the infected fleas and bugs
increase during the first few days.

"(6) The faeces of infected fleas and bugs contain virulent plague
microbes as long as they persist in the alimentary canal of these
insects.

"(7) Animals could not be infected by the bites of fleas and bugs
which had been infected by animals whose own infection had been
occasioned by a culture of small virulence, notwithstanding the
fact that the insects may be found to contain abundant plague
microbes.

"(8) Fleas and bugs that have fed upon animals which have been
infected by cultures of high virulence convey infection by means of
bites, and the more certainly so the more virulent the culture with
which the first animal was inoculated.

"(9) The local inflammatory reaction in animals which have died
from plague occasioned by the bites of infected insects is either
very slight or absent. In the latter case it is only by the
situation of the primary bubo that one can approximately identify
the area through which the plague infection entered the organism.

"(10) Infected fleas communicate the disease to healthy animals for
three days after infection. Infected bugs have the power of doing
so for five days.

"(11) It was not found possible for more than two animals to be
infected by the bites of the same bugs.

"(12) The crushing of infected bugs in situ during the process of
biting, occasioned in the majority of cases the infection of the
healthy animal with plague.

"(13) The injury to the skin occasioned by the bite of bugs or
fleas offers a channel through which the plague microbes can easily
enter the body and occasion death from plague.

"(14) Crushed infected bugs and fleas and their faeces, like other
plague material, can infect through the small punctures of the skin
caused by the bites of bugs and fleas, but only for a short time
after the infliction of these bites.

"(15) In the case of linen and other