428 KING. [Vor. XIX. 
of the yolk-nuclei that are first formed in the egg of Bufo 
since, for a time, they le in a zone half way between the 
germinal vesicle and the periphery of the egg and later draw 
near to the germinal vesicle where they gradually disintegrate. 
The only conjecture Jordan makes as to the probable function 
of the yolk-nuclei is that “they have a real physiological sig- 
nificance probably related to the construction of yolk.” 
The granular yolk-nuclei found by Foot in the egg of Allo- 
lobophora fcetida bear a striking resemblance to those found 
in the egg of Bufo (Cf. Foot’s Figs. 4-5 with my Figs. 44 
and 46). According to Foot the yolk-nuclei arise in contact 
with the nucleus, but, judging from their staining reactions, 
they are not derived from the chromatin as Calkins (14) main- 
tains is the case in Lumbricus. As the yolk-nuclei increase in 
size they become broken up, and they are either scattered in 
patches throughout the cytoplasm or aggregated at the egg 
periphery. Foot concludes that these yolk-nuclei are formed 
of “archoplasm,” and she traces them into the attraction- 
sphere, the fertilization cone, and the polar rings. Munson 
finds granular yolk-nuclei in the egg of Clemmys marmorata 
which are similar to the granular masses shown in Figs. 44 
and 46. Munson states that these structures are formed of 
“a kind of metaplasm (or archoplasm) arising in the neigh- 
borhood of the germinal vesicle through the combined in- 
fluence of the nucleus and cytoplasm. From the place of its 
formation, it diffuses or flows throughout the cytoplasm where 
it serves as a culture medium of the living substance of the 
egg; in other words, it serves as food. The true yolk-bodies 
are a secretion of the living substance of the cytoplasm.” 
Soon after the yolk-nuclei become arranged in the form 
of a ring there appears near the periphery of the egg a number 
of small, round, homogeneous bodies which stain intensely 
(Fig. 45). These bodies, as their subsequent history shows, 
are a new generation of vitelline bodies which are directly con- 
cerned with the formation of the yolk. From their peripheral 
position one might, perhaps, be inclined to think that the 
follicle cells are concerned in some way with the formation 
