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slight elevation of the temperature on the fifth, sixth, or seventh day of 
the disease. No general exanthem was observed. 
(3) Histological examination of the specific lesions and of the vis- 
cera.—Of the three foci chosen for inoculation, in two the lip and the 
palate yield similar microscopic pictures. In the nose two varieties of 
lesions are found, depending upon whether the lesion develops upon the 
portion lined by stratified or by columnar epithelium. In the former 
case the lesion is similar to that on the lip or palate. 
In a general way the lesion on the palate which can be taken as a type 
of that on a stratified mucosa epithelium suggests a lesion on a hairless 
skin from which the crust and the other superficial parts have been 
removed. When we examine in detail lesions of various durations we 
find a close similarity in them to the vaccine lesion on the skin, both in 
the cell changes and in the histogenesis of the lesion. For forty-eight 
hours after the inoculation the only change demonstrable in a small cleft 
in the submucous connective tissue which is filled by blood and fibrin, with 
an occasional polynuclear leucocyte. A few leucocytes are also to be 
found in and about the neighboring vessels and in the overlying epithe- 
lium which has closed over the inoculation wound. Later lesions show 
swelling and degeneration of the epithelial cells over a small area, which 
increases in size from day to day as the lesion spreads. If we study a 
lesion of 5 days’ duration we find at the periphery some swelling of the 
individual epithelial cells, which gives place, as we approach the center of 
the lesion, to various degenerations. In this thickened epithelium at the 
edge of the lesion we find fluid collecting between the cells in such a 
manner as to form minute chambers similar to those in the periphery of a 
skin lesion of the same duration. This is the only approach to vesicle 
formation presented by these lesions. In the center of the lesion the 
epithelial cells are quite unrecognizable, and the space is filled by fibrin, 
leucocytes, and cell detritus. There is often a rather sharp line of demar- 
cation between the swollen but comparatively normal epithelium which 
borders the lesion and the degenerated central portion. Occasionally 
islands of pathological, but still recognizable, epithelial cells are found 
in the necrotic area. 
The submucous tissue presents a complicated cell picture. The blood 
vessels are more or less prominent, in part on account of swelling and 
proliferation of their endothelial cells and in part from the large number 
of polynuclear leucocytes within them and migrating through their walls. 
The connective-tissue cells are more or less swollen and are frequently 
undergoing mitosis. A considerable number of eosinophile leucocytes 
are frequently present. Polynuclear leucocytes occur in large numbers 
but do not form such a prominent part of the picture as they do in the 
skin lesion. Besides these readily identified cells there are many mono- 
nuclear cells present which are not so easily distinguished. The majority 
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