720B 
chronic inflammation. The softened condition 
of the brain is doubtless due to a similar cause, 
the blood yielding vitiated materials for the 
nutrition of the organ. In brains of this de- 
scription the dilated and congested state of the 
veins, and the enlarged and lax condition of the 
arteries, abundantly demonstrate how sluggish 
had been the force by which the circulation is 
maintained in the capillaries, that force of at- 
traction between the blood and the nervous 
matter, by which more than by any other means 
active nutrition is maintained. 
The parts in which softening when partial is 
apt to occur in the brain may be thus enume- 
rated according to the order of their frequency 
—the fornix and septum lucidum, the corpus 
striatum and optic 1 a the mesocephale, 
the corpus callosum and other transverse com- 
missures, the hemispheres of the brain, the 
cerebellum, the medulla oblongata. 
Of the inflammatory or red softening. — 
Another form of softening of less frequent oc- 
currence than that just described possesses very 
distinctive characters. It is generally pretty 
circumscribed in extent, of a diffused redness, 
most commonly of a bright hue; the consistence 
of the part is much diminished, and it readily 
breaks up under the stream of water. Nerve 
tubes are found in it, more or less varicose and 
friable, also red particles of the blood, and many 
of those large nucleated cells commonly known 
as exudation corpuscles, within which an active 
molecular motion may be often seen. 
The red colour of this form of softening is 
due partly to the injection of the bloodvessels, 
and partly to the extravasation of the red parti- 
cles of the blood throughout the softened part. 
Sometimes the red colour is absent, although 
the lesién is essentially the same. In such cases 
the colour may be yellowish and due to the 
presence of a less injection of the bloodvessels 
and a slighter extravasation of the colouring 
matter of the blood. Dr. Bennet states that he 
has found exudation corpuscles in a softening of 
a brilliant white colour, a fact which seems to 
indicate that the products of inflammation may 
be present without discoloration, and that all 
instances of white softening ought not to be 
considered non-inflammatory. 
The researches of Dr. J. H. Bennett, of Edin- 
burgh, are among the most important contribu- 
tions to the morbid anatomy of the brain of late 
years. I think he has clearly established that 
the great characteristic of inflammatory soften- 
ing is the presence of exudation corpuscles 
about the minute vessels, and among the ele- 
ments of the softened cerebral tissue. This is in 
in the vast majority of instances accompanied 
with discoloration, which sometimes is due 
solely to the dark colour of the exudation cor- 
puscles themselves. When these corpuscles 
are not present, and especially when the soft- 
ened portion of brain is free from colour, then 
we must regard the lesion as non-inflammatory, 
the result of imperfect nutrition, or as produced 
by physical causes coming into operation shortly 
before or after death. As the same process of 
softening which involves the cerebral structure 
often extends to the minute vessels, small extra- 
NERVOUS SYSTEM. (Nervous Centres. Apnormat Anatomy.) 
vasations, constituting the capillary apoplexy of 
Cruveilhier, frequently occur where no indica- 
tions of inflammation exist ; in such instances the 
softening, although non-inflammatory, may be 
of a yellow colour from the effused colourin 
matter of the blood. _, 
1 cannot agree with Dr. Bennett in regardi 
white softenings as generally post mortem, ax 
the result of maceration in serum. The softer 
ing of very thin parts, such as the fornix an 
septum lucidum, no doubt, is frequently of # 
character. But I have seen many instances 
white softening of other parts of the bra 
which were not exposed to the physical ec 
tions calculated to produce such a change 
consistence. “g 
Inflammatory softening occurs most f 
quently in parts which are near the great vast 
lar surface of the pia mater; the convol 
and the white matter of the centrum o 
corpus striatum, and the optic thalamus are t 
most common situations of this lesion. — 
thirty-three cases collected by Durand-Fare 
the softening was situated in the convolution: 
thirty-one, and in nine of them the convolutic 
were the sole seat of softening. The fe 
table will illustrate the statement above mai 
it represents the results of fifty-three cases: 
lected from different sources, ! 
Convolutions and white substance ...... 
Convolutions alone .........eeeeseeene 
White substance alone .......+sseeeee 
Corpus striatum and optic thalamus. ..... 
Corpus striatum alone ........eeeeeees 
Optic thalamusalone .... 
Pons Varolii .. 
Crus cerebri .. 0... 00.sco00 6eWNine 
oye apes eer. ee eeeee 
Walls of the ventricles, septum ...+.+-.. 
Fornix teeter reese ee ee ee 
Cerebellum o0-0 ceecctocces esses enn 
Suppuration—From what has been sta 
the previous paragraphs it is plain that the 
important sign of inflammation of the br 
is red softening. Infiltration of pus is 
Dr. Bennett states that in no single instai 
humerous examinations made by hii 
softening be traced to the presence or in 
of pus. This is a direct refutation of 
mand’s assertion that this form of softening 
its colour to the infiltration of pus. Pus, 
ever, is sometimes collected into a cavity ii 
brain, forming an abscess. An exca) at 
greater or less size is formed in the substa 
the brain, and this is lined by a yellowish’ 
braniform layer, which resembles either lyt 
an expanded form, or the purulent ma’ 
in a less liquid form, compressed into th 
of a membrane by the accumulated liquit 
Pus in the brain is of slow formatio 
has often become collected in consi 
quantity before it betokens its presence 
symptoms. Sometimes we have the: 
nity of examining it before it has acquin 
yellow colour and oily consistence of lau 
pus. In this stage it may be mistaken f r 
malignant formation ; it is whitish, semi-st 
and sometimes mixed with streaks of DI 
Its true nature may be recognized by m 
t 
& 
ser eee weet ete 
