518 ROBERT W. HEGNER 
stages (figs. 30, 33) the group of nuclei is more often near one side, 
at the anterior pole, and the oocyte nucleus is entirely surrounded 
by secondary nuclei, the latter sometimes being several layers 
in thickness (fig. 34). Hundreds of such groups were carefully 
examined, beginning with oocytes in Stage D (fig. 14, D; fig. 26), 
but ih no case could the origin of the secondary nuclei be definitely 
determined. As the latter increase in number, they, as well as 
the oocyte nucleus, tend to lose their spherical shape and be- 
come oblong, or indented, or more or less irregular (figs. 28, 
29, 34). This may be due’to the action of the fixing solution, 
or to the pressure of one upon another, but many of them pre- 
sent shapes very suggestive of budding, or of more or less equal 
constriction into two. Some groups selected from the large 
number examined are shown in outline in figure 45. Frequently 
the space produced by the indentation of one of the nuclei is 
perfectly clear and resembles a vacuole. This suggests the 
possibility that the irregularity of the nucleus may be due to the 
escape of material from it which occupies the space formed by 
the caving in of the nuclear membrane. If this material were 
then to become surrounded by a nuclear membrane a secondary 
nucleus would be the result. 
Two other theories have been suggested to account for the 
formation of secondary nuclei. According to Will (’84) in Hemip- 
tera, Korschelt in Bombus, Henneguy in the honey-bee, and 
Brunelli (’04) in Hymenoptera they appear to come from fol- 
licular epithelial cells. Brunelli thinks they are attracted around 
the germinal vesicle by chemical action. Gross (’03) likewise 
believes from his studies on Bombus and other Hymenoptera 
that they are true nuclei, but that they originate from the 
epithelial cells which are situated among the nurse cells. This 
cannot of course be true in forms such as Camponotus where the 
secondary nuclei appear before a follicle and nurse cells are 
acquired. The other theory is that advanced by Stuhlmann 
who says ‘‘Ich wiederhole noch einmal, dass ich diese Kerne nur 
fiir ‘Dotterconcretionen’ halte.”’ 
The investigations of Loyez (’08) upon the ‘noyaux de Bloch- 
mann’ are the most thorough yet published. She studied these 
