(354) 
ous preparations of ovules at about this stage of development 
were obtained and it seems evident that the spore-mother-cell 
arises in the usual manner. The tapetum which is formed 
consists in the earlier condition of a few tabular cells which 
suffer division by periclinal walls, thus forming an axial row 
of cells. By the time that the divisions of the mother-cell 
occur the nucellus has assumed an oval form and the sporo- 
genous cell is covered by the several parietal layers of the 
nucellus. The ovule at this time is borne at the end of a 
long funicle and has almost completed its turning to the ana- 
tropous position. The integuments have exceeded the nucel- 
lus in height. The parts of the ovule are of relative propor- 
tions similar to those of Luff@ and some others. 
The divisions of the spore-mother-cell now ensue. The 
first division results in the formation of two equivalent cells 
which proceed to the second division simultaneously (fig. 83). 
From this point the development of the embryo-sac proceeds 
by the usual course. The usual structures are apparent as 
the time of fertilization approaches (fg. 8g). The synergids 
are long and narrow, their tips hyaline and striated and their 
vacuoles small. As in former cases the nuclei lie immedi- 
ately above the vacuoles and the structure above the nuclei 
to the hyaline portion is apparently reticulate. The odsphere 
resembles a synergid in size and form but differs in the char- 
acter and position of its vacuole and nucleus (fg. 84). The 
antipodals are three in number and distinctly visible at this 
stage, and show less evidence of disintegration than in some 
of the forms previously cited. Here they appear perfectly 
normal though not large. No evidence could be found, 
however, of their existence beyond the time of fertilization. 
At this time the nucellus is flask-shaped, the bulb-like por- 
tion surmounted by a long slender beak. The embryo-sac 
and its associated structures are quite small in this species of 
Cucumis; the embryo-sac in particular requiring large mag- 
nification to bring out the details of its structure. 
The polar nuclei migrate to a position just below the egg- 
apparatus, where they come into contact and probably unite. 
