No. 2.] THE OOGENESIS OF BUFO.LENTIGINOSUS. 427 
bodies grow rapidly and divide very readily both in earlier 
and in later stages of development and they are rarely found 
in groups of more than three before the formation of the 
yolk-nuclei. 
In eggs with a diameter of 0.25-0.3 mm. the yolk-nuclei 
are very conspicuous since they stain more intensely than at 
the stage of Fig. 46, and their number is much less than at an 
earlier period as several small granular masses fuse to form 
larger ones. At this stage of development the yolk-nuclei 
come to have a definite arranvement in the cytoplasm, form- 
ing a more or less complete ring midway between the nucleus 
and the periphery of the egg (Fig. 44). This is not an acci- 
dental arrangement found in a few eggs, but it is a constant 
phenomenon in eggs of a given size taken from different in- 
dividuals and preserved and stained in different ways. At 
this time the cytoplasm contains very few large vitelline 
bodies, most of these bodies having been used up in the forma- 
tion of yolk-nuclei. 
In the egg of the newt Jordan finds granular yolk-nuclei 
similar in appearance to those found in the egg of Bufo at 
the stage of Fig. 44. Jordan states that these bodies appear 
about the time that the yolk is beginning to form at the per- 
iphery of the egg “from points of independent origin,’ and 
that there are never more than nine of these structures. In 
the very young egg Jordan has found what appears to be 
“localized condensations of the cytoplasm and a consequent 
greater avidity for staining fluids,” and he finds all gradations 
between these bodies and the granular yolk-nuclei. From his 
observations Jordan concludes that “in the newt the yolk- 
nuclei always arise first as condensations of the cytoplasm and 
subsequently increase in size and complexity with the growth 
of the egg.”’ The figures given by Jordan do not show clearly 
the early development of the yolk-nuclei, although his Figs. 
5, 10-12 are sufficiently detailed to indicate that the method 
by which the yolk-nuclei are formed in the egg of the newt 
is essentially the same as in the egg of Bufo. The subsequent 
history of these bodies in the egg of the newt is similar to that 
