452 KING. Dore DIDS 
filled with a fluid derived from the disintegration of the 
odcytes. Ognew also suggests as a special process of de- 
generation, the penetration of one cell of Bidder’s organ into 
another. 
From the very early stages in the development of Bidder’s 
organ.in Bufo lentiginosus the germ-cells are surrounded by 
follicle cells which are in direct contact with the outer surface 
of the cytoplasm, since the cells never seem to develop a yolk 
membrane as do the cells of Bidder’s organ in Bufo vulgaris 
according to the investigations of Ognew. After the stage 
of Fig. 29 the egg shrinks away from its zona pellucida and 
its outline appears somewhat irregular (Fig. 27). At this 
time many of the follicle cells lie in slight depressions in the 
egg surface as if they were already beginning to enter the 
egg. It would seem as if the absence of a yolk membrane 
might make it possible for follicle cells to penetrate into the 
eggs at any stage of development, but I have never found these 
cells inside of the egg until the nucleus and the cytoplasm have 
begun to degenerate. Stages in the penetration of the fol- 
licle cells into the egg are shown in Fig. 30. The cells do 
not show any ameeboid processes, but they appear to sink 
gradually into the substance of the cytoplasm. Fig. 32 shows 
a late stage in the absorption of the egg by means of the 
follicle cells; the nucleus has entirely disappeared and all that 
is left of the egg is a small amount of deeply staining, granu- 
lar substance. 
Sometimes, as shown in Fig. 30, B. C., blood corpuscles 
enter the cytoplasm with the follicle cells and evidently take 
part in the absorption of the egg. The zona pellucida be- 
comes very irregular as the egg degenerates, and, owing to 
the pressure of the surrounding eggs, it collapses after the 
egg has become partially absorbed and evidently suffers the 
same fate as the egg itself. 
The process described above is the usual method by which 
the eggs in Bidder’s organ disintegrate in all toads under two 
years old. Sometimes in young toads, more often in adults, 
a blood capillary breaks through the zona pellucida and forces 
