146 Contribution to Knowledge of Silver-Leaf Disease 



the wall of the deformed nucleus (Figs. 13, 14). Apparently the different 

 forms of the disorganised nuclei are connected with the wandering out 

 of the chromatin grains. Here and there we can observe that the 



Figs. 13, 14. Cells from spongy parenchyma showing nuclei with sharp-pointed lobes. 



chromatin grains are outside the nucleus (Figs. 15, 16), and what is 

 more a whole line of several chromatin grains lies, in a few cases, 

 outside of the nuclear substance (Fig. 15). In such a case the nuclear 



Fig. 15. Cell from spongy parenchyma showing chromatin grains outside the nucleus. 

 Fig. 16. Nucleus from palisade cell showing chromatin grains accumulated at the 

 periphery. 



membrane seems to be very thin; or it disappears entirely in some 

 places, but this is a rare occurrence. Another reason for the view that 

 chromatin grains migrate from the disorganised nucleus is the occurrence 

 in the palisade parenchyma of disorganised nuclei which are without 



