780 THOS. H. MONTGOMERY, JR. 
knife. The counts made on the mitochondria of these figures 
‘ resulted as follows: 
Fig. 87, one hemisphere of a cell, about 10. Fig. 88, less than 
one hemisphere of a cell, 9. Fig. 89, nearly a whole cell, about 
16-17. Fig. 92, nearly a whole cell, apparently 9. Fig. 93, 
one hemisphere of a cell, 11-12. Fig. 94, one hemisphere of a 
cell, 10. 
These counts give from 9 to 16 or 17 distinct and separate 
threads. These cells were selected as the clearest in my prepara- 
tions, the ones showing the mitochondria stained most deeply and 
uniformly, and of them that of fig. 92 was the most distinct. 
There now comes up the question how these behave during 
the division of the cell body, for they lie wholly outside of the 
spindle and do not fall under its dominion. Figs. 95 and 97 
each show the mitochondria of about one hemisphere during the 
anaphase of the first maturation mitosis; a number of them 
lie more or less parallel to the spindle, others lie near the poles, 
but none are yet dividing. In the later stage of fig. 99 all the 
more strongly stained mitochondria of the cell are drawn, but 
there is still no division of them. In fig. 100, the only good 
case of this stage with mitochondria well stained, the more in- 
tensely stained ones have been drawn, and it can be distinctly 
seen that certain of those which lie parallel to the spindle are 
breaking into two at the equator, and that the others which lie 
removed from the equator are undergoing no division at all. 
It thus results that mitochondria which happen to cross the 
line of constriction of the cell body become there broken into 
two, and that the others pass bodily without division into one or 
the other of the second spermatocytes. This happens because 
they are quite unsymmetrical in arrangement and do not 
come under the influence of the spindle fibers. Further, it 
would be extremely improbable that a particular mitochondrial 
thread that does become divided would be pinched through in its 
exact middle portion. Again, the mitochondria often appear 
more numerous at one pole of the cell than at the other. (figs. 93, 
97,99). Therefore during the first maturation mitosis there is no 
mechanism except the constriction of the cell body to divide the 
