Campbell. — Studies on the Araceae. 68 1 
rapidly to many times their original dimensions, and show 
every indication of extremely active growth. The cytoplasm 
is abundant, and the small nuclei enlarge rapidly, becoming 
extremely conspicuous. At this period (Fig. 42) the enlarged 
antipodal cells so closely resemble the young endosperm that 
they were at first mistaken for them, and this led to the 
erroneous statement made in a former article. 
The walls of the antipodals become thicker, and they 
ultimately reach gigantic dimensions, being easily seen in 
sections by the naked eye (Fig. 56). This enlargement is 
accompanied by a corresponding growth of their nuclei, which 
become many times larger than those of the endosperm-cells. 
At first they show a perfectly normal structure, but later 
there are evidences of disintegration. The nucleoli become 
immensely enlarged (Fig. 59), and finally very irregular in 
form, and the reticulate structure of the active nucleus 
becomes more or less completely broken down, and shows 
many evidences of disintegration. 
From their close resemblance to the active young endosperm- 
cells, there can be no doubt that the antipodals function as 
endosperm during the early development of the fertilized 
embryo-sac. 
The great enlargement of the antipodal cells is not peculiar 
to Spathicarpa among the Aroids. Hofmeister 1 figures 
enlarged antipodal cells in Arum orientate , and the writer has 
noted the same phenomenon, accompanied by increase in 
their number, in Lysichiton. In the latter there is also the 
great enlargement and subsequent degeneration of the nuclei 
of the antipodal cells. It is highly probable that a similar 
condition will be found in other genera. 
The Embryo. 
The fertilized egg increases slowly in size, but there is no 
division of the embryo until the embryo-sac is nearly or quite 
filled with endosperm, so that almost from the first the 
embryo is completely surrounded by the endosperm-tissue, 
1 1. c., PI. VII, fig. 4 . 
3 A 2 
