242 '~ BOTANICAL GAZETTE [APRIL 
out the whole of nuclear division, and that, consequently, the entire 
process is intranuclear. 
Secondly, we note the absence of any definite chromosomes in this 
peculiar division; and equally noticeable is the failure of the chro- 
matic material to become aggregated into an equatorial plate, as well 
the want of a definite achromatic spindle. Careful counts, however, of 
the fibrous strands radiating from the centrosomes indicate the prob- 
ability of a constant number of these chromatic fibers. I have in 
many instances counted about sixteen of these radiations from the 
polar view (jig. 55), but it is perhaps impossible to determine exactly 
the correct number, on account of the great confusion of threads. I 
believe, nevertheless, that these fibrous strands of chromatic material 
represent the chromosomes, and further, that the two daughter nuclei 
each receive an equal number. 
There seems little evidence for the existence of a differentiated 
achromatic spindle, but further study in related species may possibly 
assist in determining what here may correspond to such a structure. 
It is true that in fig. 64 is shown an indefinite, intrafibrillar substance 
which might be taken for a spindle, but I am convinced that the thick- 
ness of the section in this instance is responsible for this misleading 
appearance. Careful observation reveals chromatic fibers in a lower 
plane of focus and it is their great number and close proximity in the 
background that probably causes the indefinite, washed-out appear- 
ance between the sharply defined filaments. In fig. 54 also there is 
shown a similar substance between the radiating fibers, whereas in 
fig. 55 this is not so noticeable. Fig. 50 as well shows but little 
nuclear substance other than that in the sharply defined chromatic 
fibers radiating from the two centrosomes. - 
Since all the dividing nuclear substance outside the centers is 
apparently confined to the two systems of filamentous structures radiat- 
ing from the centers, we must therefore conclude that there is no intra- 
fibrillar spindle-substance. And, since we see also that these radia- 
ting strands appear to be chromatic in their staining reactions and 
not achromatic, the only conclusion which seems possible is that 
there is no substance in the dividing nuclei of Empusa which can cor- 
respond to an achromatic spindle. I am not prepared,. however, for 
such an extreme belief, which would obviously much belittle the 
