26
Scientific Memoirs by
The average size of a series of cells which were carefully measured was
8.8µ X 7.2µ, but the variations between individual specimens was very consider
-able, the largest ones measuring as much as 10.7µ X.5µ, the smallest only
5.4µ X 5.4µ. The size .of the nuclei was much more constant to an average of
5.6µ X 3.4µ. In any case they were relatively large, and in the case of the
smaller elements the layer of cytoplasm was so thin as to cause them, in many
instances to simulate free nuclei.
Examinations under high powers also demonstrated the various stages in
the development of the growth very clearly, showing the gradual accumulation
of lymphoid elements with progressive dissociation of the normal structures of the
invaded area. The appearances presented in many of the fat-lobules of the sub
-cutaneous areolar tissue were particularly instructive (Plate III., Fig. 4). In some
places only a few scattered lymphoid and epithelioid elements were present be-
tween the fat-cells; in others distinct local accumulations had occurred; in others
such accumulations had led to separation and partial compression of the sur-
rounding cells, and in still others continuous masses of lymphoid and epithelioid
elements had entirely replaced the fat-cells throughout considerable areas of the
affected lobules. The adventitia of the lobular vessels, as before mentioned, ap-
peared in many instances to form the primary site of invasion, but in others this
was not the case, the adventitia remaining quite free even where other portions
of the lobule had been seriously affected.
In the areas of invasion of the dermal tissue proper appearances corre-
sponding with a natural injection of irregularly ramified lymphatic spaces were
in many cases most distinctly traceable. In other places the lines of invasion
had clearly primarily followed the tracks of hair-follicles or the ducts of sweat-
glands. The various stages leading to the formation of the epithelial concre-
tions occurring in the discharges of ulcerating specimens of the disease in asso-
ciation with the other form of concretions previously alluded to, could be readily
traced as connected with processes of continuous growth occurring in the tips of
interpapillary processes, or of detached portions of hair-follicles which had be-
come isolated and buried in masses of the granulation-tissue (Plate III., Figs. 5, 6).
It is unnecessary here, however, to go into further details regarding the
general structural features of the specimen, as these fully agreed with those des-
cribed by. Dr. Lewis and myself in our previous paper, and I shall therefore now
go on, to the special consideration of the characters of the peculiar parasitic
bodies present in it, and which it appears at all events possible were the primary
cause of the disease.
The specimen was primarily procured with the view of ascertaining whether
there were any evidence of the association of any special form of Bacterial
organisms with the diseased tissues. A very large number of sections were
accordingly prepared with the freezing microtome and were subsequently sub-
jected to the influence of various staining reagents—Picrocarmine, Logwood,