The Morphology of Functional Activity in the Ganglion Gells etc. 525 
larger groups of cells are found to be from fifteen to nineteen times largcr 
than the nucleus. The first point to determine is whether this is due 
to the nucleus remaining stationary while the cell body continues to 
enlarge or whether the nucleus adds actually to the disproportion by 
itsclf becoming smaller. The latter is undoubtedly the full explanation. 
In three of the series (Tables IV, VI and VII) the nucleus averages smaller 
than in the preceding group, while in Experiment 23 (Table V) it is about 
the same size. More trustworthy than this is the comparison of the 
number of individual cells whose nuclei are smaller than the smallest 
in the preceding group, occasionally ranking rather with the resting 
nuclei. For example, in Table IV, there are seven out of eleven. 
Certainly in no other place in the process do they show anything but an 
increase over the normal. It was this striking characteristic in certain 
cells of the first abdominal gangüon that first caUed attention to the 
probable existence of this type. Observation alone in favorable cases 
is sufficient to determine the fact of size disproportion (Figs. 3, 10, 15 
and 20). Frequently, these ceUs are to be notcd as characterizcd not 
only by a smaller nucleus but by a denser and deeper staining nuclear 
substance. 
This shrinkage of the nucleus and the consequent shift in the nucleus- 
plasma relation is undoubtedly the homologue of what occurs in higher 
cells in more pronounced fashion. Hodge first (1892, 1894), Mann (1895), 
Lugaro (1895), Valenza (1896), Pergens (1896, 1897), Odier (1898), 
Pick (1898), Holmgren (1900), and Pugnat (1901), in fact practicaUy 
all the investigators have noted the existence of shrunken, irregulär, 
even crenated nuclei in cells simUarly though in less degree affected, 
though their interpretations have varied widely. Hodge, Odier, Per- 
gens, Pick and Valenza correctly regarded it as significant anu indi- 
cative of an early state of fatigue. In the work on the Purkinje cell, the 
consideration of its relative state of hyperchromatism and its size rela- 
tions corroborate this view, to mention only the morphological arguments. 
After the initial increase of size (Text Fig. 5) both the cell body and the 
nucleus diminish to Stage 5 which is the Hodge type and represents the 
minimum of shrinkage. But the nucleus shrinks relatively more, so that 
while the absolute size of the ceU may be smaUer than of the resting type, 
the nucleus-plasma relation beconies greatly in favor of the cytoplasm. 
In the crayfish ceUs the nucleus is not irregulär nor uneven, the 
striking point of difference from the vertebrates which have been studied, 
nor is the contour of the cell more irregulär than may be the case in 
other stasres. But the earlier conceived idea of the total absence of the 
o 
