MKTAPHASE SPIXDLE IX FORFICULA AURICTILARIA. 241> 
The Metapliase Spindle in the Spermatogenetic 
Mitoses of Forficula Auricularia. 
€. F. F. Meek, M.Se., F.L.S., F.Z.S. 
With Plate 17. 
Introduction. 
In a paper published at the beginning of this year I have 
shown that only one generalisation has been establislied con- 
cerning the mitotic spindle, viz. that it is not a figure formed 
entirely by the action of forces at its poles. The arguments 
put forward by Hartog in support of his mitokinetic force 
pi-ove that, if this generalisation is denied, the spindle can be 
formed by no known forces. Gallardo and Khumbler have 
been compelled to accept this proposition; and all early theories 
either admit it, or are disproved because they do not admit it. 
I pointed out that in the circumstances we must collect 
data, and not attempt to explain mitosis until other generalisa- 
tions have been established. Our knowledge of the morpho- 
logical features of the cell and of the chemical nature of its 
component parts is rudimentary ; and, since we know nothing 
concerning the forces working in mitosis and concerning the 
changes undergone by the mechanism in the course of evolu- 
tion, speculation upon the subject is at present likely to prove 
abortive. The work of each decade has shown more and more 
that the cell is a highly complex entity ; and the results of 
future research may prove it to be even more complex than 
we now suspect. Recently several writers upon both chromo- 
somes and the achromatic portions of the cell have suggested 
