Germ Cells of Leptinotarsa Signaticollis. 165 



ment of amitosis when continued for a number of cell generations. 

 It has already been pointed out that the basic-staining property 

 of the cytoplasm is probably due to incomplete oxidation of sub- 

 stances which consequently remain in a reduced condition. 

 Inside of the nucleus on the other hand, the retention of the oxy- 

 dases results in a high degree of oxidation; hence the capacity of 

 this region to stain with the acid dye. 



If these changes in chemical properties are due to the failure 

 of the nuclear membrane to disintegrate periodically, we can 

 readily see how amitosis in the nurse cells is related to the pre- 

 paration of the basic-staining granules of the food stream. Further- 

 more this conclusion is in perfect keeping with the physiological 

 observations of other workers which support in every way the 

 interpretation put forth here. 



We now come to a series of phenomena which represent a most 

 peculiar form of cell activity. Shortly after the red nucleolar 

 granules are extruded from the nucleus, one notices here and there 

 a basic staining spot in the green nuclei of these cells (Figs. 27). 

 Ordinarily, this does not occur in a singly-nucleated cell, but in 

 one of the nuclei of a polynucleated mass (Fig. 25). This spot 

 increases in size and forces the green area to the periphery (Fig. 

 28) . Finally as a result of the continued expansion of the central 

 part, the original nucleus and cytoplasm become reduced to mere 

 shells (Fig. 31); but before it has reached its largest size, a green 

 area appears in the center of the central red area as shown in Figs, 

 25, 26, 29, 30, 31. About this time, or even before (Fig. 28), the 

 cell with its concentric layers usually becomes pinched off from 

 the polynucleated mass (Figs. 26, 31). Fig, 32 shows a peculiar 

 condition in which the central part (nucleus?) is dividing. 



This remarkable series of changes begins in the distal region 

 of the ovariole at about the time the first batch of eggs are half- 

 grown. Since all of the nurses cells do not pass through this cycle 

 of changes, the phenomena can not be regarded as degenerative 

 processes, nor would they seem to be concerned with the elabora- 

 tion of nutritive material, for the reason that so few cells are in- 

 volved. 



The fact that in the final stage as shown in Fig, 30, the central 



