Fie. 1. 
or 
Fia. 7. 
12. 
13; 
14. 
ILLUSTRATIONS. 
Prats I. 
A minute early lesion. ‘The epidermis is thickened over a small area, the 
result of the swelling of cells. The nuclei are large and vesicular and 
several contain the characteristic inclusions. 
. An early varicella lesion showing multiple centers of degeneration in the 
epidermis. The ballooning type of degeneration is most prominent. 
Exudate has penetrated the epidermis, separating the cells and forming 
small chambers. 
. A minute varicella vesicle presenting a defect in the epidermis forming 
its floor. The exudate contains a small amount of fibrin. Considerable 
infiltration of the underlying corium. 
. The process affecting the epidermis about the duct of a coil gland, which. 
however, is not involved. Three large multinuclear cells resulting 
from direct nuclear division are present in the degenerated portion of 
the epidermis. 
. A minute lesion taken within twenty-four hours after the first appearance 
of the eruption. Exudate has penetrated the degenerated epidermis 
forming small spaces. This represents the beginning of vesicle 
formation. 
. A typical unilocular vesicle taken twenty-four hours after the first ap- 
pearance of the eruption. The fluid filling the chamber contains a 
small amount of fibrin and a few epithelial cells which have became 
loosened in the exudation. The epithelium persisting beneath this 
chamber presents various degrees of ballooning degeneration. 
PrLate II. 
Vesicle taken twenty-four hours after the first appearance of the erup- 
tion with lense shaped chamber extending, through the axis of which is 
a hair sheath. The fluid contents of this vesicle appeared perfectly 
clear macroscopically, but contains a small amount of fibrin. Slight 
infiltration about the vessels of the corium. 
. A lesion located in the depths of a hair follicle and presenting several 
large multinuclear epithelial cells. The surface epithelium is not 
affected. 
. Two characteristic cytoplasmic inclusions situated in the epidermis. X 
1000. 
. Coarse fibers found in the epithelium forming the wall of the vesicle. X 
1000. Stained with phosphotungstic acid-hematoxylin. 
. Flaeccid, slightly clouded vesicle of two days’ duration. Large amount 
of fibrin in exudate. Epidermis involved in lesions almost completely 
necrotic. 
A large nuclear inclusion found in a sebaceous gland. Some indication 
of internal structure. X 1000. - 
Vesicle of four days’ duration. Fluid contains large numbers of leuco- 
cytes and phagocytic cells. Epidermis is commencing to grow in at 
the sides. 
Corium in the vicinity of a varicella vesicle. The pigment cell to the left 
of the capillary contains a large number of nuclei probably resulting 
from (a) mitotic division. 
371 
