STUDIES OF THE DEVELOPMENT OF PEPEROMIA HISPIDULA 37 1 
denser. In the cytoplasm throughout the whole lower portion of the 
sac there appear at this time numerous droplets of oil, varying from 
I to 6 or 7 ju in diameter. These bodies are deep black, in material 
fixed in Flemming's fixing fluid, and then sectioned and examined 
without decolorizing. They take the same color when sections of 
seeds preserved in formalin are treated with dilute osmic acid. This 
staining quality together with their behavior toward alkanna and their 
structure, leave little doubt that they are oil globules that probably 
serve as a temporary reserve food material. 
Unless fertilization occurs in an egg, which maybe indicated by the 
number or size of its nuclei and nucleoli, development throughout the 
whole embryo sac, and indeed in the whole seed and fruit, ceases 
completely. Considerable numbers of ovules in which the sacs have 
ceased development and have begun to degenerate, are seen on spikes 
where other ovules are developing normally. More rarely all, or 
nearly all of the ovules initiated degenerate before passing far beyond 
the i6-nucleate stage. 
The next evident step in the further development of the embryo 
sac after the appearance of two nuclei in the egg is the formation of the 
huge endosperm nucleus. The fusion of the 14 nuclei which give rise 
to it is usually preceded by a crowding together of these components, 
until many of them are flattened against each other on one or more 
sides (figs. 84, 86, 87). Occasionally fusion of the nuclei in pairs may 
begin while the different pairs are still far apart about the vacuole 
(fig. 83). As the nuclei of the central group, formed in the more 
usual type of fusion, become compacted those in the center of the 
group begin to lose identity by the disappearance of their walls where 
in contact. There are thus formed oval or lobed nuclei, with two or 
more nucleoli (figs. 83, 85, 86, 87). The number of lobes, and es- 
pecially the number of nucleoli, indicate clearly the number of nuclei 
that have fused. To the first fusion products, made up of 2 or 3 nuclei 
each, other single nuclei may be added or two of the fusion products 
may themselves melt together. Thus gradually, all of the 14 nuclei 
lose their individuality in the at first lobed, and often vertically flat- 
tened, primary endosperm nucleus (figs. 87, 88, 89). 
Usually, at the time the nuclei come into contact, the chromatin has 
the form of a reticulum, though at one stage there seems to be a rather 
simply folded or looped chromatin thread or skein (figs. 84, 86) . At the 
surfaces where the nuclei are in contact there is soon evident a distinct 
