The Morphology of Functional Activity in the Ganglion Cells cto. 531 
The seasonal variations of cell states and the indications of recovery. 
It is in a certain seasonal Variation that the only corrclation of the 
inner cell states with the known outward functional condition has been 
observed so far or indeed considered in the crayfish. Coinparison of 
animals of all ages killed late in the Fall gave the Impression of rather 
surprisingly advanced and general changes, more noticeable in the general 
survey in the sensory cells. Of the animals secured in the Spring, to 
control these observations, a certain number do show decidedly a more 
rested condition. On the contrary, those that do not exhibit this appear 
to be in a worse condition than the Fall animals, a Statement which is 
true particularly of the very young and probable yearhngs. These ob- 
servations would agree with the locally observed fact that a number of 
crayfish may be caught at any time during the Winter, though the ma- 
jority appear to retii’e to their bmTows. Whether, however, such varia- 
tions might not occur at other times the data is not in hand to determine. 
The point is that it affords additional evidence of the shifting states of 
the cell and indication that the recovery necessary to complete the cycle 
of activity does take place. Fimther, if the Index cells in Table I be com- 
pared, there can be no question that the high activity manifest in the 
size of the youngest recedes or further function would soon be impossible, 
so near are they to the raaximum limit. Otherwise, however, this partic- 
ular table does not illustrate the return to rest, as already indicated in 
the preceding section, and the observations above are upon abdominal 
ganglia. Localization, in the sense of implying functional demand, 
determines the amount of work and the ehance to rest. 
Just as in the Purkinje cell (1911a) a certain number of recovery 
ceUs are to be fouud in any normal animal, indicating previous activity, 
so in the crayfish these are to be expected. A peculiar type of cell whose 
significance has been so interpreted is represented in Figure 24 . The 
pericellular edema is marked, yet the edge of the cell substance does 
not show the usual fading transition but is sharply differentiated and 
compact. The periphery of the cytoplasm is not only exceedingly irre- 
gulär but for some distance in is more or less meshed with clear spaces, 
an appearance which might be expected when the achromatic reticulum 
persistent in the edema, as in Figures 17 or 21, begins to accumulate 
substance anew. As probably it is not the rule in this primitive cell for 
it to be driven as dose to exhaustion before the incidence of recovery, 
the lagging behind of the nucleus in size and accumulation of chroraatin 
would not likely be so conspieuous as in the Purkinje cell, as it actually 
