369 
amoeboid activity and phagocytosis. The exudate filling the vesicle is 
at first clear and contains only fibrin and a few degenerating or necrotic 
epithelial cells, but later large numbers of phagocytic endothelial cells 
are found in it. The active destructive process is followed at once by 
repair. The epidermis grows in, closing the defect, and the corium 
returns to its normal conditions. 
From the wider distribution of the process in the corium than in the 
epidermis and from the occasional occurrence ofa process in a blood 
vessel far removed from any epithelial focus, it seems probable spat the 
first change in the corium antedates that in the epidermis. 
The development of the vesicle is attended by the formation, about 
the epithelial cells, of numerous fibers which agree very closely with the 
fibers of Herxheimer found in the normal epidermis. It is apparent, 
however, that there is actually an increased production of these fibers in 
epidermis stretched through the pressure of the exudate. 
Several varieties of atypical lesions occur. The exudate may break 
into the wall of the vesicle and separate the horny layer so that a 
secondary vesicle is formed which includes the original, or lesions may 
occur practically without exudation. Some lesions are confined to the 
depths of hair follicles without the surface epithelium being affected. A 
certain number of lesions are infected by bacteria as the result of which 
they become pustular. In such lesions there is more or less destruction 
of the papillary layer which accounts for the scars frequently following 
an attack of varicella. 
Specific nuclear and cytoplasmic inclusions are found in all varicella 
lesions and their appearance constitutes the earliest change observed in 
the tissues. They occur in epidermal cells and in various cells of the 
corium. The nuclear inclusions stain red or purplish by the eosin- 
methylene-blue method, and vary in size from 1 to 6 microns in diameter. 
The cytoplasmic inclusions stain a deep purple and a central granule is 
_ apparent in many. ‘They are seldom found measuring over 4 microns. 
A conclusion has not been reached concerning the nature of these inclu- 
sions in varicella and no important evidence has been found in favor of 
the hypothesis that they are parasitic organisms. 
Tnoculations of the cornea of the rabbit and the skin of the monkey 
with the contents of varicella vesicles have in all cases yielded negative 
results. 
REFERENCES, 
1. Buehmiiller, A., 1886. Varicella, eine Krankheit sui generis. Mittheil. des 
Vereins der Aerzte Steiermarks. Ref. Virchow-Hirsch, Bd. (1886), II, 44. 
2. Czarkert, 1869. Zeit. d. Wundiizte Oesterr. Ref. Ziemsen’s Hneyclopaedia, 
II, Am. Edit. 
3. Fleischmann, 1870. Die Stellung der Varicell zur Variola. Wiener Med. 
Woch., N. 51. 
4. Fleischmann, 1871. Ueber Varicella und Varicellen-Impfungen. Arch. f. 
Derm u. Syph. (1871), XIII, 497. 
