NOTES ON SrOEOZOA— in. 
207 
conspicuous karyosome represents a kinetic (locomotor) com- 
ponent ? Moreover, another idea prevalent in the writings of 
the adherents of this school, which is strongly to be deprecated, 
is that of contrasting, as two opposed constituents, kinetic and 
generative components of the nucleus. These two things are 
not strictly comparable or opposable at all. On the one hand, 
the essential kinetic components are the achromatic elements 
— centrosome, centrodesmose, and so on ; and in all proba- 
bdity these take part in effecting the division of generative 
cliromatin as well as of vegetative (trophic) chromatin. And, 
on the other hand, where a separate kinetomicleus is present, 
which may be regarded as standing in a special relation to 
the locomotor activities of the 'I’rypanosome, there is no 
reason whatever for supposing that the chromatin of this 
nucleus is less generative in character than that of the tropho- 
nncleus.^ In short, I cannot share the above view of the 
locomotor or kinetic natui-e of the karyosome as a whole 
at all; it is the contained centrosome, not the 
chromati n-n ncleolus, that brings about the division. The 
so-called Ilantel-Figur ” is really the result of the gradiial 
(passive) separation of the two halves of the karyo.some as 
the centrodesmose extends." 
It seems to me very much better to return to the earlier 
manner of regarding the karyosome, which has been well set 
forth and discussed by Siedlecki (34 and 35 j, namely, that it 
is an organella, whose principal function is to store up reserve 
chromatin — and particularly trophic as distinct from genera- 
tive chromatin — for use as and when required by the nucleus, 
or, as the case may be, for elimination if not required. This 
theory undoubtedly fits in best with the known variations in 
' Tliis point was enipliusised hy me so long ago as 190(1 in my 
analysis (40) of Scliaiulinn’s celebrated work on tlie parasites of the 
little owd. 
- Tlie same interpretation is in all probability to be ap 2 )lied to the 
" nncleolo-centrosome ” (Keuten) of Euglena, esjiecially as Hartmann 
and Chagas (loc. cit .) liavesliown that 2 )romitotic division of tlie karyo- 
some, by means of a centrodesmose, occurs in another Englenoid, 
Peranema t richoj) horum. 
