534 
David H. Dolley 
hat.« In fact, the lack of direct observation of chromatin discharge 
appears to be his main argument from the morphological side, and if 
it be universally true, justifiably so. That such an observation is not 
directly afforded by the primitive cells of Canibarus, and probably still 
more unlikely by those of Ascaris, I graut freely, nor is it afforded so 
far as niy observations on nerve cells go by presumably even more dif- 
ferentiated cells, even so high in the scale as the spinal ganglion ceUs of 
man. That this mnst have a bearing upon the interpretations of other 
primitive cells than nerve cells there can be no question. Bnt it is a 
different matter for the' acnie of differentiation, the cortical cells of cere- 
bellnm or cerebrnm. Of course this is not an observation of the active 
passage of chromatin, save to the extent that the disappearance of chro- 
matin from within the nnclear membrane is associated with a reappearance 
in the plasma, but is not that snfficiently convincing when it happens 
at several independent stages of the process? How eise is to be inter- 
preted, when the resting nncleus has absolutely no formed chromatin save 
in the karyosome, that in the hyperchromatic stages it masses up within 
the nnclens after the onset of activity and after the cytoplasm is fnll and 
then later disappears, coincidently with an obvious need for this excess 
in the cytoplasm as shown by its peripheral dissolntion? How eise is 
the same thing to be interpreted in the stage of secondary reappeai'ance, 
where starting with no chromatin at all in the cell outside the karyosome, 
the cell advances along with a size increase to a formation inside and 
about the nnclear membrane? Or why in the final stages of a continuous 
process should the karyosome undergo disintegration, whose fragments 
have beeil observed at various points toward the nnclear membrane and 
collected just within it? The passing out of these particles as such has 
not beeil followed bnt after this a tertiary renewal of extra-niiclear chro- 
matin has beeil repeatedly observed in many exhausted animals to persist 
with a chroniatin-free nncleus. Or why should the basic staining sub- 
staiice be precipitated within the nnclear membrane in an active recovery 
as it sonietimes is? In this connection, an observation originally made 
by Holmgren (1900) of the basophile character of the nnclear mem- 
brane in activity is worthy of note as occnrring in periods of increased 
nnclear activity in the Purkinje cell. These are not merely objective 
differences in distribution occnrring haphazardly and interpreted on 
their face valne. It is measurement placing theiii at discrete and con- 
stant stages of a continnons process which gives tlieiii theh significance. 
This is true of what formed chroniatin occurs within the nnclear 
membrane. As a matter of fact, the visnalization of the chromatin in 
