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of camels dead of the disease, and disinfection of clinical thermometers used
on the sick. Early in the disease, Liq. Acid Carbolic : (B. P.) 2 drachms
twice a day may be of use ; the recovered camel received this as well as the
others.
43. Remarks.—The first severe lesion is not enteritis but peritonitis;
this conclusion is justified by clinical observations and by the post mortem
appearances ; the distribution of the enteritis shows it to be entirely due to
complete stricture of the colon which in turn is caused by productive peritonitis.
The disease is not due to foreign body, lipoma or Volvulus; nor to irritant
"poisoning" since the stomachs and first part of the intestine are generally
healthy.
Minute examination of fresh tissues was not possible under the circum-
stances.
Negative results were obtained by inoculation of defibrinated blood of sick
camels into pigeons, camel, ox, guinea-pig and rat.
No gross parasites could be found in the lesions.
44. FILARIA EVANSI.—The following is a brief summary of the results of
investigations made to date :—
The adult filariæ are white worms from 3 to 9 inches in length and live
in the lumen of the blood-vessels, particularly the arteries ; the females discharge
the embryos direct into the circulation. Adults are occasionally found in
extra-vascular positions. Of the arteries, the spermatic is the usual situation
in which adults are found ; next the pulmonary artery ; and they may also be
found in various other arteries of the viscera.
The embryos are found in the- circulating blood and are easily demonstrated
on examination of the fresh blood taken from the tip of the ear ; the objective
should be of low power, a two-third or a Zeiss A. The preparation must be a
thick one, far thicker than that used in the diagnosis of Surra. The embryos
resemble a snake in shape and show violent movements of wriggling, coiling
and uncoiling.
Their length is about ten times that of a trypanosome.
In infected camels the embryos may be demonstrated on any day at any
time of the year.
They may also be found without difficulty at any hour of the day ; they
are sometimes more numerous at one hour than another, but this "periodicity "
is not regular and in many cases the number of embryos in the blood appears
to be about the same throughout the day.
45. When filarial embryos are found in the blood of a camel in poor
condition, they cannot be blamed as a cause of disease until it has been shown
that the animal is not suffering from the chronic form of Surra.
When throughout the day, filarial embryos are so few that they can only
be found after considerable searching, they do not cause any loss of condition
and the animal appears quite healthy.
When, however, the embryos are in large numbers (say 50 or more in
each 5 c.m.m. of blood, or several in each field of a thick blood-film under a
two-third objective) there are enough to cause loss of condition. Of a number
of camels with filariasis only a small minority will show the embryos in such
large numbers.
Surra and filariasis are often found in the same camel. This has greatly
complicated the investigation of the latter disease.
A camel sometimes shows an insignificant number of filarial embryos for
months and years in its blood and remains in perfect condition ; sometimes,
however, the number suddenly increases until they are very numerous and in
these cases a loss of condition has soon been apparent ; during the increase the
temperature is slightly above normal.
I have seen no other constant symptom of a severe infection with F. evansi
except loss of condition and strength, and its consequences ; the duration of
the disease therefore depends entirely on the conditions under which the animal
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