1900] ENDOSPERM AND EMBRYO OF PEPEROMIA 3 
cytoplasm. This group may appear at the lower end of the 
embryo-sac, in the middle near the wall, or center, or above, and 
near or even in contact with the egg (espn, fig. 3). 
The remaining peripheral nuclei retain their position near the 
wall, at first as naked nuclei in the thin layer of cytoplasm, but 
later each of these and a small portion of cytoplasm is separated 
from the great mass of cytoplasm in the embryo-sac by a flat 
saucer-shaped wall (fn, figs. 3, 7,9, 72, 13). Nowhere was there 
noticed any tendency of a number of these to collect in a basal 
position, or anything in their behavior to suggest their homology 
with the antipodals of the typical angiosperm embryo-sac. 
The short top-shaped stamens bear two pollen sacs each. 
Certain pollen grains (three or four in a section showing fifteen 
fertile ones) remain with unthickened walls, but apparently are 
not used for the nourishment of the fertile ones. The nucleus of 
the finely reticulate-walled pollen grain divides to two at a 
time soon after the formation of the tapetum in the embryo-sac 
of the same flower. The pollen grains are shed after the embryo- 
sac has reached the four-nucleate stage. They lodge on the 
large abaxial lobe of the carpel (st, fig. 7), and grow downward 
through a conical mass of small-celled conducting or nutritive 
tissue to the fusion canal of the carpel, and thence to the micro- 
pyle (pt, fig. 1). Just when the division of the generative 
nucleus occurs was not made out with certainty, but in cases 
where the pollen tube had just reached the embryo-sac the 
pollen-tube nucleus was seen at its very tip, and a single large 
generative nucleus, with cytoplasm about it, at the level of the 
nucellus. In other cases of about the same age there were 
apparently two generative nuclei. 
No indication of a sterile prothailial cell was discovered. 
The pollen tube often extends some distance into the egg, and 
after its entrance two nearly similar nuclei are found within the 
egg. The exact fate of the pollen-tube nucleus and the second 
generative nucleus was not determined. 
_ For a considerable time after its entrance the male nucleus 
lies in the egg near or even in contact with the female, but without 
