( 387 ) 
of Luffa, Trichosanthes and Bryonopsis it will be observed 
that the starch appears before the fusion of the polar nuclei, 
though in the case of Apodanthera the fusion takes place 
before the formation of the starch. In Cucurdzta the fusion- 
nucleus is seen in the midst of the starchy cytoplasm. 
The source of this starch is a matter of much interest. 
Schleiden” states that the starch is brought to the ovule of 
Cucurbita by the pollen-tube, but here we find starch in the 
embryo-sac before the pollen-tube appears. D’Hubert' de- 
scribes a condition in Péy/locactus in which starch is formed 
first in the antipodals and later disappears from these and 
accumulates in the free cytoplasm of theembryo-sac. Lloyd® 
reports an abundance of starch in Galiwm surrounding the 
polar nuclei and also in the antipodal cells. He finds it also 
in Dvodia and Houstonza to some extent, though in the former 
it appears first in the antipodals and later in the endosperm. 
In either case it appears to be wanting until after fertilization. 
It will be noted that in Cucurézéa and the other cases cited 
the polar nuclei or the fusion-nucleus by their size and chro- 
matic features exhibit a high degree of metabolic activity. 
The antipodals in some cases are prominent ( 7r7chosanthes) 
and in others (Cucurbita, Apodanthera, Luffa and Bryonop- 
s?s) either partially disorganized or merely vestigial. Hence 
it is evident that the antipodals are not physiologically active 
at this stage. In those cases in which the fixation was ac- 
complished by osmic acid mixtures, the presence of much oil 
was apparent in the tissue of the nucellus immediately sur- 
rounding the embryo-sac (Cucumus, fig. 84). The quantity 
of oil is greatest nearest the embryo-sac. The evidence at 
hand indicates that the oil is absorbed from these cells by the 
embryo-sac and becomes transformed into starch in the cyto- 
plasm surrounding the polar nuclei. 
The physiological equivalence of fats and carbohydrates 
is a fact well known. Pfeffer” points out that, during the 
germination of the oily seed of the cucumber, glucose is 
formed abundantly, and oil is formed from glucose in the 
ripening seed of /ticznus, but from starch in the endosperm 
