XX]
RÔLE OF THE RAT
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decumanus community, Mus rattus—the more domestic species—being subsequently attacked. Later the disease appears in epidemic form in man. (Chart 5.)
The seasonal prevalence of bubonic plague in rats
is marked, and is not due to a periodicity in their reproduction, but is connected with periods in which fleas are most numerous.
The ancients were well aware of the connection between plague and the rat. In the Bible