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the question as to how rats could cause the disease in horses for the
food would rarely, if ever, be soiled with the blood of these animals.
It therefore only remained to be tried whether the excreta of rats—in
whose blood the infusorian was present at the time of its collection—
could cause the disease when mixed with grain. In 1892, experiments
were undertaken at Poona on the Deccan plateau, where the disease is
not enzootic, and where the difficulty of producing it was fully recog-
nised on account of the dryness of the situation; these, as expected,
proved negative. At a later date—during the latter half of the hot season
and the rains of 1893—further experiments with the same end in view
were carried out in Bombay, where the climate is favourable from its
humidity, and the disease is enzootic. From these, positive results were
obtained, which points to the probability of a number of the surra cases
in Bombay being contracted through the ingestion of rats' excreta
mixed with the corn.

                         G. I. C. P. O.-No. 59 I. G. C. V. D.-30-4-94.-250.