J. F. SHIRLAW 349
extensive. Liver and kidneys highly congested; bladder, a few petechiæ;
spleen, few surface petechiæ and hæmorrhagic. Kidney, highly congested ;
lymph glands hæmorrhagic ; blood clots poorly.
Horse 312.—No enteritis ; definite meningitis, slight adhesions between
pia mater over entire cerebral cortex and cerebellum ; pia firmly adherent to
cerebral substance ; slightly gelatinous, somewhat organized, exudate; cord,
congestion of meningeal vessels ; kidneys markedly congested ; spleen, slightly
enlarged and darker in colour; liver mildly congested; urinary bladder nor-
mal.
These cases were all peracute. It will be seen that there was a diversity
of lesions both in the internal organs and central nervous system, although
they all conformed to a general type. Apart from the constant, yet variable,
lesions of the brain and cord, the lesions of the internal organs, with the excep-
tion of the kidney, were not uniformly present. Neither gastro-enteritis,
acute splenitis, failure of the blood to clot, acute hæmorrhagic lymphadenitis,
hæmorrhagic cystitis, nor hæmorrhage in the parenchymatous tissues could be
looked upon as a constant feature. It is difficult, if not impossible, to account
for the presence of these lesions in some cases and not in others.
Streptococcus melanogenes (Schlegel) was isolated from the cerebral tissue
of two cases, from the cerebral cortex and blood of one case and from the
blood alone in another case. When the fact was observed, in the earliest
case, it was considered that this organism might be significant, as a secondary
invader, in the development of ' septicæmic' lesions. This hypothesis was
quickly dispelled when it was found impossible to isolate it with constancy
and when it appeared in cases which were definitely non-" septicæmic " in
type. No pathological significance, even of a secondary nature could, there-
fore, be attributed to this organism.
No matter what the intensity of the cerebral and spinal lesions, hæmorrh-
age, either punctiform or extending to a depth of several millimeters, was
always present in the grey matter, throughout the cerebral cortex, the cere-
bellum, the brain stem and the cord. This was undoubtedly a constant fea-
ture. The cut surface of the brain was, usually, yellowish in colour or marked-
ly reddened.
The liver of all cases showed some degree, however mild, of icteric stain-
ing and parenchymatous degeneration. The liver is not so commonly affected
with vascular changes, although occasionally hæmorrhages in the substance
are found, and the myocardium and the lung substance may be similarly
affected.
In several acute and subacute cases whose post-mortem examination the
writer witnessed, the writer came to the conclusion that the constant lesions
are :—congestion of the meningeal vessels, with loss of lustre of the meninges
and some mild thickening, both of the brain and cord; icteric discolouration
of the liver; hæmorrhages of varying degree, usually punctate, of the grey
matter, and renal congestion. The meningeal vessels appear peculiarly sclero-
tic in all cases.
Cystitis appears, in a certain number of cases. There is obviously present,
in every case, an early paralysis of the bladder (catheterization is always
necessary). Some horses, as the result of retention, rapidly develop cystitis.