STUDIES ON GERM CELLS 519 
secondary nuclei or ‘pseudo-noyaux’ as she calls them, in four 
species of Bombus, two species of Vespa, and one species of 
| Xylocopa. They were found to resemble true nuclei in their 
fully developed condition, but all stages were observed between 
these and the very small vacuole-like bodies from which they 
apparently arise. The theories of their origin by budding off 
from the germinal vesicle and by the emigration of epithelial cells 
are considered by Loyez to be untenable. The conclusion is 
reached that they originate from the germinal vesicle, follicular 
epithelial cells, and nurse cells not by budding or the emigration 
of entire nuclei ‘‘mais resultent d’une coagulation de substances 
venues du dehors al’etat fluide on granuleux et modifiées par le 
cytoplasme de l’oeuf.” (p. 100). In old oocytes the secondary 
nuclei were found to change in structure so that they resemble 
nuclei which are undergoing synapsis, and, since all stages 
between the typical secondary nucleus and a homogeneous 
globule were observed, Loyez decides that they transform into 
deutoplasmic spheres. 
The presence of these secondary nuclei in certain insects and 
not in others can be regarded as a sort of precocious diminution 
of nuclear substances. The loss of chromatin by passage through 
the nuclear membrane and its identification as chromidia in the 
cytoplasm has been reported by a number of investigators as 
taking place in the nuclei of many different kinds of cells during 
what is known as the resting stage. During ordinary mitosis 
only a part and sometimes the smaller part of the nuclear chro- 
matin is concerned in the formation of the spireme, the rest being 
cast out into the cytoplasm with the other nuclear contents 
when the membrane breaks down. These substances’ become 
scattered and dissolved in the cytoplasm. Just before the 
maturation divisions occur, it is customary for the germinal 
vesicle to liberate into the cytoplasm a considerable part of its 
contents, including granules or small masses of chromatin which 
become scattered amid the yolk globules and disappear. The 
diminution of nuclear substance therefore seems to be a wide- 
spread process. That the formation of at least part of the second- 
ary nuclei in the oocytes of certain insects is likewise a nuclear 
