340 D. J. HAMILTON. 
Changes in the Neuroglia. 
This was not so markedly altered as one would @ priori 
have expected ; still in many instances its protoplasmic nuclei 
were much more abundant than in sections taken from normal 
portions of the same cord. ‘The manner in which the new 
corpuscles were produced could not be made out with satis- 
faction, but the probability is, from what was seen, that they 
also resulted from fissiparous division. 
Changes in the Blood-vessels. 
In the neighbourhood of the ligature numerous and large 
extravasations were noticed, probably mechanically brought 
about in operating on the cord. In the pia mater surround- 
ing the cord, and in the processes which run into it, immense 
numbers of round clear corpuscles were observed in the 
perivascular spaces and tunica adventitia of the vessels. 
They were also abundantly seen within the vesseis, adhering 
to the inner coat, and many of them could be actually 
noticed in the wall. What these corpuscles were I think can 
hardly be a matter of doubt. They were the leucocytes of 
the blood, which, after adhering to the inner wall of the 
vessel in greater abundance than under normal conditions, 
made their way through its coats, passing into the perivas- 
cular space and adventitia, and there constituting pus-cor- 
puscles. Throughout the grey substance numbers of similar 
corpuscles could be seen scattered indiscriminately, and there 
is every probability that these were also leucocytes which 
had wandered from the neighbouring vessels. 
Having thus summed up the characteristic alterations in 
the individual tissues, their consideration shows us that the 
inflammatory condition in the spinal cord, like inflammation 
in other organs, is not one simple process, but is a combina- 
tion of phenomena dependent on the individual characteris- 
tics of the histological elements entering into the construction. 
of the part. The formation of colloid bodies from the axis 
cylinders, and their subsequent transformation into pus-cor- 
puscles, were so clearly demonstrated as to leave little or no 
doubt on the subject, and it was a somewhat remarkable fact, 
in confirmation, that at the seat of greatest inflammation the 
division of the swollen axis-cylinders was most abundant, the 
segments becoming rapidly round, transparent, and granular, 
and further subdividing into pus-corpuscles. Where the 
irritation was not so great, the divided parts became round 
and translucent, but remained as colloid bodies, 7. e. bodies 
which had a colloid-looking aspect. Much has been written 
