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The nuclear inclusions appear at first as minute eosin-staining granules 
about 1 micromillimeter in diameter, situated in the nuclear sap. The 
nucleus may contain one or several. A clear space is formed about each 
nuclear inclusion and the nuclear network recedes from it. The inclu- 
sions rapidly increase in size and stain more intensely. They are most 
often rounded, but may be elongated or irregular. In some instances 
the nucleus is affected only about the inclusion, at which point it is 
greatly distended while the remainder appears normal. (Pl. III, fig. 
18.) Very irregular and lobulated nuclei are thus produced in the’ cells 
of the corium. In the epithelial cells the whole nucleus becomes 
distended, the chromatin and nuclear network retracts to the periphery, 
leaving the interior about the inclusion clear. Direct nuclear division 
follows these changes, and each of the resulting nuclei usually contains a 
characteristic inclusion. These inclusions may attain a diameter of 6 
microns when rounded and 9 microns when stretched out in elongated 
form. Some appear dense and homogeneous, while others are granular 
- in character. Indefinite, deeply stained points are occasionally to be 
made out in them. In some instances minute granules of similar sub- 
stance are grouped about a large inclusion. In one case in which the — 
knife had passed through a sebaceous gland in excising the lesion, the 
nuclet were ruptured and the inclusions here showed characteristics not 
apparent elsewhere. (PI. II, fig. 12, and Pl. IV, fig. 25.) They were 
evidently composed of a plastic substance as they had a sharp though 
irregular outline with rounded projections suggestive of a flowing motion. 
They consist of a sharply contoured body, delicately reticulated in 
structure. Certain ones showed a central, deep-staining granule. A 
certain number of nuclear inclusions are found which either are attached 
to the nuclear membrane or are protruding through it. They show a 
marked constriction where they pass through the membrane. A large 
proportion of these inclusions present the form of an irregular, reticulated 
mass without definite contour. Although these inclusions take the red 
in preference to the nuclear stain, they stain deeply by other methods 
so that they would not readily be distinguished from chromatin. 
The cytoplasmic inclusions stain a densé purple by the eosin and 
methylene blue method, and measure from 1 to 4 micromillimeters in 
diameter. They are often found lying against the outer surface of the 
nuclear membrane, but may also occur between cells free in the connective 
tissue or in any position in the cytoplasm. They are constantly present 
in moderate numbers in the epidermis and in the cells of the corium of 
the early lesions, but are usually less numerous than the nuclear inclu- 
sions. They always possess a sharp contour, are most often rounded, 
but. are occasionally irregular, and have usually a deeply stained central 
_ point. The occurrence of nucltar inclusions protruding through the 
nuclear membrane suggests a possible method of origin for the cyto- 
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