Campbell. — Sttidies on the Araceae, III ’ 331 
are nearly hemispherical masses of tissue whose upper cells are larger and 
indicate the beginning of the papillate hairs which later are so conspicuous 
at the base of the funiculus. As the ovule enlarges, these hairs become 
much more evident (Figs. 4, 5), and the ovule itself assumes an oblong 
form. The apex, which develops later into the nucellus, is somewhat 
attenuated, and there is visible a slight enlargement below the young 
nucellus, which marks the beginning of the first integument. 
At this stage there could be seen a single rather large sub-epidermal 
cell, from which is later developed the single embryo-sac. During its 
further growth the ovule becomes strongly bent. The second integument 
develops and the first (inner) integument rapidly grows up above the 
nucellus, forming the micropyle. Later, the outer integument grows much 
faster and extends beyond the inner one. 
The nucellus, as in most Araceae, remains relatively small. The cells 
at its apex become elongated, and periclinal walls arise in them, so that 
the young embryo-sac (Fig. 5) is sunk rather deeply in the tissue of the 
nucellus. 
From a study of the younger stages of the embryo-sac, although the 
actual division was not seen, it seems likely that the primary archesporial 
cell usually divides once by a transverse wall, the outer and smaller cell ( t ) 
representing the tapetum, which undergoes no further divisions and later is 
destroyed. The inner and larger cell develops directly into the embryo-sac. 
It is possible, however, that the outer cell represents a second embryo-sac 
and not a tapetum, as in one case (Fig. 11) there was found above the 
embryo-sac a cell containing several nuclei, which recalls the development 
of the secondary sacs met with in some other Araceae. 
The development of the embryo-sac up to the time of fertilization 
shows nothing peculiar. The polarity is strongly marked, the two primary 
nuclei lying at opposite ends of the sac. These nuclei are not very large 
and are of the usual type (Fig. 9). 
The subsequent divisions proceed as usual, and the eight resulting 
nuclei are distributed in the ordinary fashion. The egg-apparatus, antipodals, 
and polar nuclei do not differ in any way from the ordinary angiospermous 
type (Figs. 10-14). The eight nuclei are much alike in size and 
structure. They stain readily and each is provided with a conspicuous 
nucleolus. 
The egg-apparatus becomes clearly evident at the micropylar end of 
the sac, while at the chalazal end are the three antipodal cells. The upper 
polar nucleus moves to the lower end of the sac where it fuses with the 
lower polar nucleus to form the endosperm-nucleus (Figs. 13, 16). 
Previous to the union of the two nuclei they are surrounded by 
a pretty well defined mass of granular cytoplasm (Fig. 12), which becomes 
less conspicuous after the fusion of the two nuclei. The details of the 
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