The Morphology of Tunctioiial Activity iu the Ganglion Ceils etc. 
505 
and 21). Consequently, the only limits that can be determined for tlic 
cell are the original ones. Fiirther, confirmation of the inherently intra- 
cellular character of this apparently extracellular edema is given by 
the results of the measurements. Fortunately in the large motor type, 
edema begins at a comparatively much later period than in the others 
and, in fact, to the extent of activity to which they have been driven, 
they Show relatively very much less, in the figures used, practically none. 
The course of the size changes was largely determined from this group, 
in which the outlines of the cell were thus definite. In the others, which 
were measured to some extent from both points of view to test the point, 
the more exact identity of the course of their curves with those of the 
first group resulted when the measurements were made to include this 
apparently pericellular edema. Finally, such an appearance as in the 
nearly exhausted cell (Fig. 22) admits of no other opinion or procedure. 
Here there is only a vestige of cell substance left around the nucleus, 
suspended within the pericellular capsule. This represents what is left 
of the cytoplasm whose place has been taken by the water y menstruum. 
In the final stages, a perinuclear edema is offen observed, as is shown 
by Figures 7, 16 and 17. 
This Figure 22 represents the ultünate limits of the edema combined 
with the disappearance of chromatic and achromatic substance, which 
will make sufficiently clear without much discussion the intermediate 
course of tlieii’ combined and progressive effects, as illustrated by the 
figures. From its beginning in pericellular rifts, the edema progressively 
increases, an appearance which becomes more marked by the association 
of peripheral paling and disappearance of chromatic substance. Further 
along it becomes very apparent within the cytoplasmic substance, first 
from a loosening up of the density of this, then from actual vacuolation 
and reticulated structure. Again, however, it is to be noted from Fi- 
gures 14 or 19 that though there is a consumption of substance peri- 
pherally from near the beginning of the process, for a considerable period 
there is a more rapid formation, so that the cell substance proper under- 
goes an actual increase, as in Figures 15 and 16 or in Figure 20. After 
this point the loss of cell substance begins to add appreciably to the 
wasted appearance. The absolute increase of cell substance uncom- 
plicated by peripheral consumption is best shown in the first and 
second (motor) series. 
Further details relating to the chromatic substance remain to be 
next indicated. In a highly differentiated ceU such as the Purkinje cell 
of the cerebellum, the description of changes outside of size is principally 
