“361 
lying the vesicle and in almost every type of cell here represented. These 
inclusions are associated with cell changes similar to those already 
described in the affected epidermis. The nuclei become distended and 
tend to divide by amitosis without subsequent division of the cytoplasm. 
Therefore, early changes of this type are found constantly in the corium as 
well as in the epidermis of the varicella lesion. It seems probable that 
the changes in the corium antedate those in the epidermis, for they are 
always present and often well marked in the earliest and most minute 
lesions. 
Further changes occur in the corium at first appearing chiefly in and 
around the blood vessels. The process in more advanced in the neigh- 
borhood of the epidermal foci, but slight changes occur over much larger 
areas. ‘The endothelial cells lining the small blood vessels present various 
degrees of proliferation as shown by the presence of numerous mitotic 
figures. Immediately around the vessels are collections of cells of which 
the most numerous have a large vesicular nucleus and more or less 
basophilic cytoplasm. It seems probable that these ‘cells are of endo- 
thelial origin, arising from endothelial cells in the lymph spaces and 
vessels adjoining the blood vessels. In favor of this view is the fact 
that numerous mitotic figures occur in the cells lining these lymph 
vessels. Later in the process these endothelial cells become phagocytic. 
Mingled with these cells are a few lymphoid cells, and an occasional eosin- 
ophile, but the polymorphonuclear leucocyte is not represented. 
In addition to the early cell changes already described, more advanced 
degeneration is found in cells in the vicinity of the affected vessels. The 
degeneration is not general; only scattered cells are affected. In some 
instances an entire cell appears hyaline and_ stains intensely. In other 
cells a form of nuclear fragmentation has taken place and the chromatin 
is scattered throughout the cell in the form of minute deeply stained 
globules. Portions of disintegrating cells are found occasionally. The 
destruction is often so far advanced that it is impossible to determine, in 
single instances, the type of cell affected, but it seems certain that the 
cells previously described as of probable endothelial origin are frequently 
destroyed. Changes in the corium like those already deseribed are found 
in all early lesions. 
Tn lesions taken at a later stage, during the formation of the vesicle 
in the epidermis, a more extensive process is found in the corium. The 
endothelial cells, although still most numerous about the blood vessels, 
are not confined to this locality. Large numbers are found scattered 
through the corium beneath the affected epidermis ; however, the number 
of these cells migrating in the tissue varies considerably in different 
lesions. 
It is not uncommon to find the capillaries and small vessels dilated 
just beneath the vesicle. The lymphatics also are dilated in some 
instances but, with the exception of those which occur immediately about 
. +4 Re 
