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extending from the end of the visible " tail."* I had no reason to suspect the presence
of ciliæ on the head; indeed it was quite possible to understand the varied movements
of the parasite without any such agency being required. I found not the slightest
sign of " two fin-like papillæ on each side—one where the neck commences and one
where the tail begins "—although I looked with much care at a specimen where Dr.
Evans detected them. Dr. Evans and I also differed as to whether their movement
can be called spiral, he maintaining the negative view and I being convinced that
their movement is as much of that nature at times as can be expected from organisms
with so open a corkscrew shape. I have since seen movements which are certainly
spiral, when the weak and more slender organism from dog's blood is trying to drag
a mule's corpuscle away from a rouleau, and I find that in dried and stained specimens
the organisms retain their subspiral form of the body and markedly spiral form of
the tail. However, apart from these minor points open to discussion, I contend that
we have ample grounds for the view that Surra and Relapsing Fever of mules are
but different manifestations of the same disease. In each inquiry the disease has
been studied by an officer specially selected for the duty and able to devote time
and attention thoroughly to it, and in the Rangoon investigation there have been the
special advantages of Dr. Evans' researches having paved the way and indicated
lines of inquiry, of longer time available, and of fewer climatic disagreeables to
contend with; he had no time to observe a single case throughout its natural course.
But there is here something more than would result from differences in powers of
observation of workers and in efficiency of appliances; evidently Surra among horses in
the Punjab has not quite the same symptoms as Relapsing Fever among mules in British
Burma. It is possible that, as climate has a marked effect in generation of the
disorder, so too it may influence their manifestations in places differing so much in
climate and surroundings as Rangoon and the Trans-Indus territory, and therefore
I consider we are justified for the present in considering that they bear about the
same relation to one another as Anthrax among horses in India does to the " Horse Sick-
ness " as seen in South Africa, and both to the very rare form of Anthrax seen among
horses in Great Britain. Thus we may provisionally speak of the " RELAPSING FEVERS
OF EQUINES " of which the British Burma disease is certainly one and " Surra " pro-
bably another, always retaining in mind that future researches will almost for certain
establish the identity of the two affections; for they agree in a number of important
respects, being very like one another in symptoms and in the characters of the parasite
found in the blood, also in their communicability from one animal of the affected
species to another by inoculation and by ingestion, and to the dog by inoculation and
feeding on the flesh of the equine animals which have succumbed to the disease.
7. In some minor respects the Tonghoo disease has been found to differ from
that in Rangoon, but there is an element of uncertainty here. At Tonghoo congestion
of the brain and its meninges has been noted in an exceptionally large number of
cases, and blood extravasations in the cranium pressing on the brain have also been
found. Although not prepared to deny that in acute cases (of which there seems to
have been a large proportion at Tonghoo) brain congestion is present, I am inclined
to consider it rare and to accept its frequency of record at Tonghoo with reserve, for
I have ascertained that no proper instruments for opening the cranium were available
there, this operation, which requires special care and delicacy of manipulation, being
done by a butcher with the aid of an axe. The blood extravasations may have been
caused in this process, or have resulted from blows given to the head by the animal
when on the ground " dying hard," or possibly be the coagulated contents of the
sinuses of the dura mater, the arrangement of which parts in the mule is different
from that in man and would hardly be familiar to a medical officer who had not
specially read up veterinary anatomy. Again the diagnosis of fatal cases at Tonghoo
was not always certain, and there may have been cases of true Apoplexy or Anthrax
here and there intermingled with those of Relapsing Fever.
8. In comparison of the mule disease with Relapsing or " Famine Fever " of man,
we find that there are a number of points of resemblance, but that the differences also
* These differences between the parasite as described by Dr. Evans and myself must be considered as possibly the
result of the fact that the descriptions of the same thing observed under the microscope by independent observers seldom
agree. This is simply the result of "many men having many minds," and of all microscopes not being alike in definition
and penetration.