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the latter occurs no more in one sex than in the other, indeed, my most persistent case
of it was in a stallion ; œdema of the limbs took place only in a very few of my cases,
whereas it was found a frequent feature of Surra. I have never noted " a nasal
discharge more or less tinged with yellow " such as was observed by Dr. Evans, nor did
I find yellowness of the conjunctiva and petechiæ on it remaining throughout the attack as
reported to him ; on the contrary, I found the mucous membranes as a rule pale in the
stage of least fever, yellowish in that of active parasite invasion, and the petechiæ
remarkable for their periodicity, the membranes being absolutely free from them at times,
and at other phases of the disease the seat of them; that dirty colored state of the
conjunctiva complicated with the presence of purplish petechiæ which Dr. Evans noted
as characteristic of Surra was constantly observed by me especially in the earlier phases
of the. disorder, but, although this is very significant when present, there are stages of
Relapsing Fever when it is not to be found. I have never seen swelling of the sub-
maxillary lymphatic glands so intense as to lead to sub-maxillary abscess although this
is mentioned as taking place in the Trans-Indus cases ;* moreover I have almost
constantly found the other lymph glands enlarged, a feature not noted in Surra. The
fever cannot be associated in direct relation with the amount of work done by the
animal before he is admitted to hospital; work or no work, you get the characteristic
thermographic tracing from an affected animal. There also is a difference with
regard to the appetite of the patient, possibly in direct association with the ulceration
of the stomach found so frequently in the Burma mules, but not (as autopsy shows)
absolutely dependent on it. Dr. Evans, in his cases, which were not thus complicated,
found that, after the primary refusal of food, the animal remained " capricious with
regard to the grain," usually taking all the grass. I find that, although the mule may
refuse gram when feeling very much out of sorts from height of the fever, he, as a
rule, eats his food freely and his fodder excessively ; indeed he will remain eating
away at the latter all day long in a surprising manner, varying it occasionally by
taking a little earth from the stable floor (central passage) or by consuming his own
dung. Sometimes there is extreme greediness for food, exceeding even that of the
healthy mule. Also in almost every case where I examined the fresh urine I found
it acid, whereas Dr. Evans always found it alkaline in the four cases which he tested.
This was an important difference in results upon a question where error would not be
likely to creep in. When we consider also that Surra is not specially described in
association with deficiency in power of the hind limbs and with marked and regular
febrile relapses, we will readily accept the opinion that the diseases are not absolutely
identical. Further, in marked contrast with the almost complete absence of definite
lesions observable post-mortem in the Trans-Indus cases, are the conditions noticed in
Burma, which are numerous, varied, and sometimes extremely marked. We must also
note that there are differences between the Surra parasite as described and the Relapsing
Fever orga,nism as observed by me. There are points in Dr. Evans' description of the
parasite in which I am unable to confirm his observations; thus I should describe their
action on the corpuscle as rather one of tearing and pushing or dragging than of sucking.
I have not been able to mark any preference for the surface over the edge of the
corpuscle, and, although their meeting in pairs lengthwise to form apparently one body
has been seen by me, it proved extremely rare. In stained specimens, however, I
found it more frequent than I at first supposed. I preferred to examine them in the
fresh blood instead of in serum obtained after the blood had coagulated, in which I failed
entirely to observe 'them in the generality of cases without staining. I looked in vain
for the " round body tapering in front to a neck" as described by Dr. Evans, for I
found that their bodies are thick at one part, from which they gradually diminish in size
in either direction, terminating in one abruptly to form a blunt end by which they
adhere to the corpuscle which part is somewhat straight and rigid, whereas towards
the other end they taper in such a manner as to produce a sub-spiral long part which
sometimes is seen uncurled and lashed about freely like a whip. This " tail" is
certainly slender in relation to the general size of the parasite, and I could neither
under my highest available power (1/10th), nor from movement of the blood constituents,
obtain any indications leading me to inter the presence of a colorless flagellum
* Dr. Evans at Dera Ismail Khan found the swelling of sub-maxillary gland and discharge of mucus from the nose
in four cases only out of fifty.