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Basile exactly coincide with what I have found in Ctenocephalus felis; I have
examined over 400 cats in Madras and have never found them infected with
any such parasite.

EXPERIMENT V.

Is THE BED BUG CIMEX ROTUNDATUS THE TRUE INVERTEBRATE HOST OF THE
PARASITE OF ORIENTAL SORE ?

      In order to settle this question beyond dispute, I bred a number of bugs
through three generations in Madras and took them with me to Cambay.
They were fed regularly during June, July and August on the case mentioned
above, some in the vicinity of the sore and others at distant parts. In order
that there may be no misunderstanding with regard to my feeding experiments,
I wish it to be clearly understood that a bug cannot possibly dislodge the para-
sites when it inserts its proboscis into the margin of a sore. Its proboscis is
not long enough as the parasites are deeply situated, so that the blood it
sucks up, can only come from that which is circulating at the spot. Bugs
will not feed on the surface of a sore which is discharging parasites. This was
definitely settled by feeding bugs at the margin of a sore, and then examining
their stomach contents immediately afterwards. The large macrophages or
free parasites were never found. Although, in a few of the bugs, unchanged
parasites were found, no development was seen in about 250 examined. My
attention was next directed to the probable explanation of the failure of the
parasites to flagellate in the bug. Early in my investigation I heard of a case
of Oriental Sore in a Parsee boy who came to Cambay for the first time in the
beginning of December 1909, and who left Cambay about January 5th, 1910.
On returning to Bombay he contracted a mild attack of small-pox, and about
three months after leaving Cambay, a small red spot was noticed on his cheek.
This slowly developed and eventually proved to be a true Oriental Sore; later
two other sores formed on his body. There could be no doubt regarding the
time of the year when this boy contracted the disease. This at once led me to
make a careful enquiry into the histories of those people who had had occasion
to come to Cambay for short periods, and it was definitely found that about
95 per cent. of the sores were contracted during the cold season which extends
from the middle of October till the end of February. Having ascertained these
facts, I at once decided to continue my feeding experiments with bugs and to
simulate as near as possible the cold weather conditions; the bugs after being
fed, were kept in a small tin box surrounded with ice. These experiments
were begun on July 25th, 1910, and on August 8th, on dissecting one of the