1899] OOGENESIS IN PINUS 273 
stages of prothallial cells. From this point the development is 
so extremely rapid that, in over three hundred preparations, less 
than a dozen nuclei showed stages intermediate between figs. 2 
ad zz. One of these is shown in fig. 6, . 0. (The proteid 
vacuoles, ~, bear a striking superficial resemblance to nuclei.) 
In this nucleus nearly all the chromatin is in the form of 
micleoli, A few linin threads are present, and associated with 
them is a very small quantity of chromatin. In other nuclei of 
about the same age, jigs. 7, 8, no linin is visible, and all the 
chromatin is in the form of nucleoli. The greater number of 
these nucleoli stain blue with -cyanin and erythrosin, but some 
‘tain red. The mere size of the nucleoli has no influence upon 
these reactions. I have not felt it safe to rely upon staining 
teactions for identifying chromatin, but have depended upon a 
close morphological series leading up to undoubted chromo- 
Somes. After all trace of the original linin network has disap- 
eared and all the chromatin is in the form of nucleoli, another 
rather peculiar linin network appears. This and all the nucleoli 
Stain intensely with iron-alum-haematoxylin. At first sight it 
Would seem that we are dealing with a chromatin network, but 
if the second application of iron-alum be sufficiently prolonged, 
only a few of the nucleoli remain black, the stain being com- 
pletely extracted from the network and from the rest of the 
Aap (fig. 71). If acid fuchsin be added to such a prepara- 
= the network and the decolorized nucleoli stain red. A later 
ie ss which the decolorizing has not been carried so far, 1s 
nes in fig.r2. Details from nuclei in slightly later wie 
the ap 72 are shown in figs. zg and 75, in which nearly a a 
Gc. coli are arranged upon the linin threads. Soon a co 
... network begins to resolve itself into a — : 
Out the n., us leaving the nucleoli scattered irregularly throug 
“Rucleus. Some of the nucleoli contribute to the granular 
certain ‘ While others migrate from all directions toward a 
of the ea usually at the center, or a little above ee 
has ucleus, In fig. 76 the network, while still distinguishab : 
Sun to break up, and nearly all of those nucleoli whic 
