DEXDROSO.A[A RADIAXS, EHRENBERG. 
157 
nncletis under certain circumstances breaks up and is dissi- 
pated in the cytoplasm, we are reminded of the condition, 
long ago described by Grnber, of the meganuclear fragmen- 
tation in the ciliata., Oxytricha and Lacrymaria. An 
alternative hypothesis, however, might be put forward to the 
effect that the condition we have observed is not disinte- 
gration but construction of meganuclens; that the scattei’ed 
ofrannles we have observed were not cast out from the meg'a- 
nnclens, but are in process of formation in the cytoplasm, and 
will be added to the nuclear bands. 
This alternative hypothesis will be considered more fully 
in a subsequent paper, bnt whatever hypothesis we adopt the 
study of the sections exhibiting this fragmented condition 
confirms most definitely the statements we have made above 
— that (1) there is no true nuclear membrane, and (2) that the 
granules of chromatin are not connected by a plastin net- 
work. 
Micronuclei. 
The micronuclei of Dendrosoma have not been previously 
described. Their distribution in the arms and stolon varies 
a good deal, and it seems very probable that they are not 
constant in position but move about in the arms and stolon, 
driven hither and thither by the protoplasmic currents. On 
this point, however, we cannot speak with certainty as we 
have never been able to recognise the micronnclei in the 
adnlt living specimens. We have been able to distinguish 
them in some of the living gemmulae. 
'I’liey are not difficult to see in some of the ordinary stained 
whole mount preparations, although the crust of foreign 
bodies adherent to the pellicle sometimes interferes with the 
clear definition of the smaller internal structures. 
'I'he micronuclei may occur both in the arms and in the 
stolon. We have not observed them at any time very close 
to the distal extremity of the arms, although in one or two 
cases we have seen one or two micronuclei lying just beyond 
or close to the distal termination of the meganucleus (fig. 50, m., 
VOL. 54, PART 2. NEW SERIES. 12 
