308 T. H. Morgan 
In regard to the last point, it should be noted that the only other 
alternative” would be to assume that the accessories unite in the 
male to produce one, or two, chromosomes less ‘than in the female. 
If this were true, however, there would be a heaping up of chro- 
mosomes in every generation unless all of the accessories were 
ejected from the sexual egg. 
The discovery of Meves that in the spermatogenesis of the bee 
functional and rudimentary sperm are produced ‘invites direct 
comparison with the somewhat similar facts in the phylloxerans. 
Meves has shown that at the first spermatocyte division the centro- 
somes move to opposite sides of the cell, a somewhat irregular 
spindle figure appears and the chromatin mass assumes the form 
of granules (chromosomes). ‘There is no subsequent separation 
of the chromosomes into two plates. [In fact, all present remain 
in the cell, which pinches off nevertheless at one pole a small non- 
nucleated mass of cytoplasm. At the second spermatocyte divi- 
sion the centrosomes move apart, the granular chromosomes 
appear again, and this time divide, but the cytoplasmic division 
that follows is very unequal. One of the resulting nucleated cells 
contains only a small amount of cytoplasm—the other large cell 
alone differentiates into a functional spermatozoon. ‘Thus in the 
bee only one of the possible four spermatozoa found in other ani- 
mals is produced. Mark and Copeland have also later obtained 
closely similar results for the honey bee. A somewhat similar 
series of changes takes place i in the egg of Vespa germanica, accord- 
ing to Meves, and his main points have been confirmed by Mark 
and Copeland for Vespa maculata. Here also the first spermato- 
cyte division is abortive, but at the second division there is an 
equal division of the cytoplasm (as well as of the nucleus) and two 
functional spermatozoa result. 
Concerning the interpretation of these results Meves points out 
that, since the male bee develops from an unfertilized egg that has 
extruded its two polar bodies, it must contain the reduced number 
of chromosomes; hence one division of the spermatocytes suffices, 
2 The fact that one rejects as not worth considering the view that chromosomes may be absorbed 
and disappear in this way shows how strong a hold has the idea of the continuity of the chromosome- 
material. 
