4 BOTANICAL GAZETTE [JULY 
fusing with it (figs. 3, zz). Its presence in the egg seems, 
however, to have an important influence on the other contents of 
the embryo-sac. At the time of its entrance the group of eight 
nuclei, each with a single nucleolus, is usually found in the cen- 
tral or upper part of the embryo-sac near the egg, surrounded by 
a considerable mass of cytoplasm, but not separated from each 
other by cell walls (espn, fig. 3). Soon after this the walls of 
certain of these nuclei are seen to be flattened against each other 
(espn, figs. 3, 6), and a little later still the group may consist of 
one or two larger, elongated, constricted nuclei, each with two 
nucleoli, and six or four normal-sized nuclei each with a single 
nucleolus. These larger nuclei have been formed in each case 
by the fusion of two of the original nuclei of the group. The 
first one or two of these fusion nuclei form centers to which the 
other nuclei of the group draw up closely and fuse on to add 
their bulk to that of the larger nuclei. Finally a very large 
nucleus is formed, with at first several normal sized nucleoli, and 
later fewer very much larger ones or a single one (espn, figs. 6,7): 
The wall of this large nucleus shows at first several projecting 
lumps or knobs, each indicating the portion contributed by one 4 
of the fusion nuclei (espn, figs. 4, 5,6, 7, 8—a series of sections of 
the same group). The line of contact of the walls of the fusing 
nuclei is at first evident by the darkly stained region where the 
two peripheral chromatin nets press against each other (espm,_ 
jigs. 5, 6,7). Later the lumps on the wall gradually smooth 
out and the chromatin net becomes evenly distributed about the 
periphery of the usually transversely elongated nucleus, which 
lies in a pretty dense mass of cytoplasm just below the oospore 
(espn, figs. 7, 8). 
From this time on this nucleus behaves like the endosperm 
nucleus of the typical angiosperm embryo-sac. It sometimes 
begins ‘its development before any activity is noticed in the 
‘fertilized egg, except that the wall of the latter becomes more 
distinct and the sexual nuclei flatten against each other (fig. 72)+ 
In other cases the sexual nuclei fuse during the fusion of the 
endosperm-forming nuclei (fig. 7). The endosperm nucleus 
