16 Campbell.—Studies on the Araceae. 
The antipodal cells increase considerably in size (Fig. 40), 
and the contents become denser. At the same time there is 
a marked increase in the size of the nuclei, which show 
a coarsely granular appearance, and stain strongly. Some¬ 
times they exhibit an appearance indicating that they are 
about to divide, but no cases were seen where they had 
divided in the unfertilized sac. Later, as we shall see, there 
is a division of these cells, similar to what was observed in 
Aglaonema. Hofmeister describes and figures a great increase 
in the size of the antipodal cells in Arum orientate, but gives 
no account of their nuclei, nor does he seem to have found 
any cases where the antipodal cells subsequently divided. 
The Endosperm. 
The formation of a solid endosperm is also characteristic of 
Lysichiton , but unfortunately, here also, the earliest stages 
were missing. The embryo-sac soon becomes filled with a 
solid tissue, whose cells are rather smaller, and have denser 
cytoplasm at the basal part than at the apex. The cells 
surrounding the embryo (Fig. 44) are larger, and the granular 
cytoplasm is mainly restricted to the neighbourhood of the 
nucleus. 
While the endosperm has been forming, there has been 
a marked growth of the integuments. The outer integument 
now extends beyond the inner one (Fig. 43), and the base of 
the latter has thickened a good deal. The embryo-sac is still 
separated from the inner integument by several layers of 
nucellar tissue, and the base of the ovule is very much 
thickened, so that, as in Aglaonema , the embryo-sac con¬ 
stitutes only a small part of the bulk of the ovule. 
While the endosperm has been forming, the antipodal cells 
also increase very much in bulk, and undergo division, so that 
they form a large and conspicuous mass of tissue at the 
base of the embryo-sac. Sometimes they are very sharply 
separated from the endosperm-cells above them (Fig. 45), but 
this is not always the case, and not infrequently it is not easy 
