418 BOTANICAL GAZETTE [JUNE 
the essential contact, but brings the tube within the influence of 
another attraction which immediately directs it to the oosphere. 
The discharge of a male cell seems to be attended by disorgani- 
zation and rupture of the tip of the tube (figs. 79, 20, 24), as 
observed by Schaffner in Sagittaria vartabilis3 In fig. 19 the 
second undischarged male Cell may be seen in the end of the 
tube in a disintegrating condition; and fig. 2¢ represents a case 
of a remarkably persistent tube and an undischarged male nucleus, 
the latter being distinctly nucleolated, as late as the second 
division of the embryo. The synergid not disorganized by the 
pollen tube persists for some time, as is usual, its nucleus being 
shown in figs. 20, 22, 2}. 
During fusion the sex nuclei hold no definite position in 
reference to each other, as is evident from figs. 79-22, where 
certain details concerning nucleoli and chromatin bands may 
also be noted. It is evident, thererefore, that the position of 
the fusing nuclei holds no relation to the plane of the first 
division of the oospore. 
In figs. 20 and 27 the structures figured by Guignard as cen- 
trospheres are represented. In these special cases no other 
structures in the cell bore any resemblance to them, but they 
were not seen except occasionally in connection with the nuclei 
in an advanced state of fusion. As no effort was made to 
demonstrate them, however, this testimony has no special sig- 
nificance. Their frequent association with nuclear phenomena 
in the higher plants certainly requires explanation, whether the 
current homology and function be established or not. 
DEVELOPMENT OF THE EMBRYO. 
ee <Tesore. division the oospore enlarges, elongates, and is not 
always axially attached to the sac wall (fig. 23). At the same 
_ time the nucleus enlarges and establishes itself at the free end 
ee of the tell Aga consequence, the first division, which is always 
a transverse, results in a small apical cell and a comparatively large 
Bes somewhat vesicular basal cell. This | basal cell and 3 
: zs oe ~ 23 — x97. 
