MEDICAL ASPECTS of PLAGUE.]
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taking place, granular débris and broken-down cells being seen here. The glands show these
changes in varying degree ; in some there is merely slight engorgement with some disten-
sion of lymph-vessels, in others there is wide distensión of both kinds of vessels, with some
amount of hemorrhage into the gland tissue ; whilst in others again there are many hæmor-
rhagic areas which may occupy half or more of the gland, and it is in these glands that break-
ing down is usually seen. In a septicémie case, the glands which have not the characteristic
plague appearance, shew under the microscope either slight engorgement or normal features.
With regard to the remaining organs, the appearances described under the bubonic form
apply also to the septicémie form of plague.
G.—THE PNEUMONIC FORM.
A section of lung-tissue, apart from a pneumonic area, shows great engorgement of all
large blood-vessels, and of the alveolar capillaries as well, and patches of hemorrhage into the
alveoli around these engorged vessels are seen scattered about. In a pneumonic area three
zones can be made out. At the circumference there is intense engorgement of all vessels,
including alveolar capillaries, the alveoli are full of blood, and the hemorrhage is so intense
that many of the alveolar septa are broken down, entirely absent, or represented by mere
shreds. Within the circumference is seen a zone, in which the alveoli are intact and are
completely filled with well-stained cells, so that there is no interval between the alveolar walls
and their contents ; and at the centre is one universal mass of similar cells, and the cellular
infiltration is so extreme that the walls of the alveoli are scarcely visible. Such is the general
arrangement of the pneumonic patch, although there may be alveolar hemorrhage in parts
of either the middle or central zone.
Under a higher power the alveoli of the circumference are seen to be completely filled
with blood corpuscles, and there is scarcely any appearance of fibrin, or none at all ; in the
middle zone the alveolar contents consist for the most part of catarrhal epithelium with
some white and a few red blood-corpuscles, and a little fibrin or none at all, whilst the dense
central mass of cells consist of catarrhal epithelium and leucocytes with some granular
débris. Thus the pneumonic area has the appearance of very extreme lobular or catarrhal
pneumonia.
The walls of the bronchial tubes, as well as of the large veins, show great engorgement,
and there are hemorrhages into the vein-walls. Blood and catarrhal cells may be seen in
the finer bronchi, but the bronchial mucous membrane is scarcely altered, there being at most
a little cellular proliferation. There are the appearances of acute pleurisy over those pneu-
monic areas which project upon the surface of the lung, with hæmorrhages beneath the pleura.
The bronchial glands show engorgement of blood-vessels, some hæmorrhage into the
gland-tissue and distended lymphatic vessels ; but in some cases these conditions are only
slightly marked and the glands looked nearly normal. The remaining lymphatic glands
in the body looked either normal, or presented the characters described above to a slight
extent.
With regard to the other organs, the description given under the bubonic form of plague
applies here also, except that generally engorgement and hæmorrhage are less marked.
D.—THE PLAGUE-BACILLUS IN SITU.
Sections of the various organs and lymphatic glands were prepared to show the plague-
bacillus in situ ; they showed best when stained with Löffler's méthylène blue or carbol-
fuchsin, but they could not be demonstrated with Gram's method.
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