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tender on manipulation. These conditions continue to increase until the
fourth day; the tumour may measure three or four inches in one direction
by two or three in the other, and be raised to the extent of an inch or
more above the surrounding tissues, from which it can be lifted.
According to the amount and the nature of the inoculated blood, so
will these symptoms rapidly develop themselves, until, after a period of
from four to thirteen days in the majority of cases, the tumour will
be found to have become less tense and tender; and when this is noticed
a microscopical examination of the subject's blood reveals the presence
of the infusorian. After this the tumour gradually disappears, and
the symptoms of surra are present, and run through their ordinary
course.

Symptoms of Inoculated Surra in Bovines.—To Dr. Lingard is
due the credit of having demonstrated the possibility of producing
surra in bovines, by the subcutaneous inoculation of blood containing
the infusoria, taken from the horse.

The symptoms noted at the seat of inoculation in the horse occur
also in bovines, and a few days after inoculation the infusorian appears
in the blood, and we have the symptoms of a mild paroxysm of surra.
Two or even more paroxysms may occur, but they are usually of a
mild character. After these mild paroxysms, in the majority of cases
the animal seems to be in perfect health, and no infusoria are, as a rule,
detected in the blood by microscopical examination, so that we should,
if we trusted to this method of examination alone, be led to the belief
that they had completely disappeared. Such, however, is not the case.
We inoculated guinea-pigs with the blood of a bull in which surra
had been produced, but in the blood of which no infusoria had been
detected for a considerable time,—83 and 165 days,—but strange to say
the inoculation was followed by virulent surra and the guinea-pigs
died.

Blood taken from the same animal produced no results when
inoculated into guinea-pigs, after 234 days, 267 days, and 356 days.

One bull was in perfect health 512 days after inoculation, and we
decided to subject him to re-inoculation with virulent material. The
result was negative, and he seemed to be protected. The course of
the disease in bovines may be summed up as follows:—One or two
mild paroxysms during which the infusoria are few; intermissions;
considerable loss of condition; recovery of health and condition.

Symptoms in the Sheep and Goat inoculated with Horse
Surra.—The disease behaves in a peculiar manner in the sheep. There
is little disturbance attributable to the action of the infusorian, which
appears to be unable to develop in the blood. The infusorian sometimes
develops in the fluid in the tunica vaginalis testis. Although the