Irving Hardesty. 95 
ing cell. This variety is about as numerous as the third variety men- 
tioned and is evidently a transition form. The nucleus though of the 
vesicular type appears at times somewhat ‘smaller than that of any of 
the preceding varieties. 
There should be mentioned under this class a variety of cell which is 
questionably a neuroglia cell at all (J, Figs. 8 and 4). Though sur- 
rounded by a definite rim of cytoplasm, the nucleus of this cell is con- 
¥ 
Fic. 4. Small area from longitudinal section showing different types of neuroglia 
cells and the general direction and arrangement of the neuroglia fibers with reference 
to the nerve fibers and ‘‘neuroglia cells.”” The colors represented are the same as in 
the preceding figures. Nucleus i is transplanted from a neighboring field and sub- 
stitutes a nucleus of type e. 1—leucocyte. x 940. 
siderably smaller (4 y to 6 » in diameter) than that of any of the above 
varieties. The chromatin of its nucleus is more evenly granular and 
more compact and therefore the nucleus stains more deeply than those 
referred to as vesicular. The cytoplasm forms a thin ring about the 
nucleus, sometimes thicker on one side, and its granules are not so 
coarse as in the cytoplasm of the neuroglia cells. In quite a few in- 
stances cells resembling these have been noted in the blood-vessels, at 
times situated among the red blood corpuscles (Fig. 1) but more often 
close to their walls. A study of the white blood corpuscles in the prepa- 
