ig0 8] BURLINGAME—PODOCARPUS 167 



which seem to be of different material because of the considerable 

 difference in depth of staining. 



The spirem gradually becomes denser and ramifies all through the 

 nucleus (fig. 11), the nucleolus disappears, and finally the spirem 

 breaks into elongated loops, which arrange themselves into a tangled 

 mass at the equatorial plate. The exact method of division wasjiot 

 made out owing to the close tangling of the long chromosomes. In 

 the anaphase the chromosomes appear as twenty-four straight 

 elongated rods of about half the length of those entering the mitosis 

 (fig. 12). 



As the chromosomes approach the poles, the polar ends draw 

 together and the others spread out, so that the daughter nucleus 

 usually has a concavity on the polar side. The chromosomes gradu- 

 ally lose their density and put out processes on one side or the other 

 to fuse with those put out by neighboring ones, thus establishing^ 

 sort of reticulate structure (fig. 13). This gradually passes back into 

 the stage shown in fig. 7. In the reorganizing nucleus one large 

 nucleolus may appear or several small ones, but I did not attempt to 

 discover the origin of them or their relation to one another. 



When the cells have reached the mother cell stage, they break 

 loose from one another and round up in the usual manner. As already 

 remarked, the mother cells killed and fixed very poorly, so that only 

 a very meager and perhaps uncertain account of them can be given. 

 About the time the mother cells round up many of them begin to 

 abort ; this abortion seemingly may occur as late as the young spores. 

 Up to this time and on to the time of the divisions in the young micro- 

 spores the development of the sporogenous tissue seems to be nearly 

 simultaneous. 



After the mother cells have rounded up, the nucleus soon passes 

 into a condition in which its contents stain so nearly uniformly that it 

 has not proved possible to disentangle its separate constituents. If 

 stained deeply, it appears absolutely uniform, and if the stain be 

 then slowly and gradually drawn, the homogeneous appearance gives 

 way to a sort of pebbled one. Sometimes it looks as if this might be 

 due to the parts of a large and long spirem being crowded closely 

 together. This interpretation is strengthened by the fact that in some 

 cases one can see what looks like the end of a loop pushing out the 



