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bugs, a nymph approaching its last ecdysis, about twenty pairs of actively
dividing flagellates were recovered. There could be no doubt as to the origin
of these flagellates, for in the first place they were found in a bug which had
been bred in Madras and brought to Cambay, and secondly, although I have
examined between 2,000 and 3,000 bugs from different parts of India, I have
never yet found them to contain flagellates, other than those obtained as a
result of feeding experiments.

      Having proved that the parasite of Oriental Sore can, and does, reach the
stomach of the bug C. rotundatus when it is fed on the peripheral blood, and
that when such bugs are kept at a suitable temperature (from 22° to 25°C.) the
parasite will develop into a flagellate; I decided to feed a large number of
bugs on the case, and then to take them down to Bombay and to feed them on
suitable people there. Through the kindness of Surgeon-General Bannerman,
the then Director of the Bacteriological Laboratory of Parel, Bombay, I was
able to feed these bugs on the Laboratory peons. Though they were fed for
about a month, and since then a year has elapsed, none of these men developed
any sores. I returned to Cambay and fed another series of bugs on the same
case and on taking them to Bombay they were fed on other suitable people.
These experiments, however, also failed. There were no young nymphs among
the bugs used in these experiments, almost all being adults. On returning to
Cambay for the second time, I found that the sore was now useless for further
experiments as the parasites had disappeared. I was therefore compelled to
search for another case, and a suitable one was not found till December 1910.
In the mean time I examined a large number of cases but unfortunately none of
them were suitable for experimental purposes. The new case had no less than
five sores, four situated on the right arm, and one on the dorsum of the left
foot: he had already had two the year previously. On puncturing the sores
particularly those on the arm, they were found to be extremely rich in para-
sites, numbers of the polymorphonuclear leucocytes being infected. A large
number of bugs were obtained from Bombay and were fed on the boy's right
arm, at a distance from the sores, so they could only ingest parasites in the
circulating blood. Here again it was unfortunate that, except for one tube of
bugs, all the rest were mature insects. I decided to dissect 100 adults and to
find out what percentage became infected. The dissections were carried out at
intervals from one to five days after the last feed, and I found four bugs con-
taining parasites, some in an unchanged condition still in leucocytes, and all
the intermediate stages shewing the formation and extrusion of the flagellum
and the multiplication of the resulting flagellates, up to the long mature
forms. The remaining bugs, some 200 in number, were taken to Bombay and

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