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elevated temperature has fallen, and in some oases has attained normal or
even sub-normal limits. The visible mucous membranes are clean, and the
conjunctival petechias begin to fade; the pulse, however, will be found to
be weak and thready in character, but the appetite excellent, and in fact if it
were not for the loss of flesh and slight oedema of the extremities, there
would be little to show that the animal was ailing. But unfortunately this con-
dition does not continue for any length of time, for again the temperature is
elevated ; in the course of a few hours the thermometer registers a still higher
degree, the animal is dull and dejected, and by the following day the visible
mucous membranes present a yellow tinge; large ecchymoses dark in colour
appear on the conjunctival membranes ; the action of the heart is irrit-
able, the pulse full and quick, or at times intermittent, and regurgitation may
be observed in the jugulars; the breathing is quickened, and the individual
respirations shallow ; on watching an animal in this condition, it may be noticed
that it takes seven to eight very short inspirations, and these are followed
by a much more prolonged and sonorous one ; at the same time the breathing is
more abdominal, than thoracic in character. On examination of the extremities,
it will be found that the swelling and oedema have increased considerably,
and that on the under-surface of the abdomen, where it was previously con-
fined to the sheath, it has now commenced to spread forward along the subcu-
taneous tissue between the skin and the muscles. During the whole of this
time the appetite will have varied little, and the evacuations will be only slightly,
if at all, altered in character. In the blood a repetition of the previous events
takes place, the hæmatozoa make their appearance, and run up to a maximum,
and again suddenly or gradually disappear according to the length of the fever
period. These periods alternating with and without fever may go on for a
considerable time ; the progress of the disease is variable, and greatly depends
upon the condition of the animal attacked, the weak ones succumbing very
rapidly ; but each bout of the fever brings with it as a rule an increase in the
severity of the symptoms. There is augmented yellowness of the membranes,
fresh crops of petechias on the conjunctival, a collection of gelatinous material
at the inner canthi, which at times becomes red in colour from an admixture
of blood, and which on microscopical examination is found to contain a varying
number of the Surra hæmatozoa ; increased swelling and oedema of the extremities
and abdomen, which now extends between the fore limbs and up the chest.
During this time the wasting has been steadily progressive, especially the muscles-
of the back and those surrounding the hip joint and the glutei.
Towards the termination of the disease, it will be noticed that an animal is
disinclined to move, and when made to do so, there will be manifest loss of power
over the hind quarters, somewhat similating a slight partial paralysis, and the
hind quarters of the animal reel from side to side. In connection with this it may
be noted, that there is frequently present paralysis of the sphincter ani, and a
dilated condition of the anus. These symptoms taken together, point to some
interference with the normal functions of the spinal cord in the lower dorsal
and lumbar regions, and is probably due to pressure caused by an exudation
within the spinal membranes. In many cases shortly before death the heart's
action becomes exceedingly violent, shaking the whole frame at each beat,
so that the sound can be heard at some distance from the animal. In some
of these cases the animal may suddenly drop dead. In others, the emacia-
tion and weakness become so pronounced that the animal falls to the ground,
and after a short bout of struggling, succumbs to the disease. In other cases,
again, the animal falls to the ground and appears to be suffering from acute pain,
struggles violently, sweats bedew the body, and the respirations are very
hurried. The struggles soon exhaust the patient's strength, and for a time it lies
quiet ; soon however the struggles commence again, and this continues until death
occurs.
B.—Those which have acquired the disease by inoculation.—Twenty-four
hours after the subcutaneous injection of a small quantity of Surra blood, in
the great majority of cases, a small, circumscribed, and somewhat raised, swelling
is noticed at the seat of inoculation ; after forty-eight hours the tumour has
increased in size, and is accompanied by some oedema ; it presents a certain
amount of tension of the parts involved, and is generally tender on manipula-