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1909] MCALLISTER—EMBRYO SAC OF SMILACINA 209 
necessarily result in the lily type of embryo sac, even though the nuclei 
seem to be of the same size and vitality. So long as the spore retains 
its individuality as such, we can expect each spore to develop into a 
separate gametophyte, and not till this individuality is lost can we 
expect to find more than one spore entering into the structure of a 
single gametophyte. This absence of division walls, however, may 
very well lead directly to such joint organization of a gametophyte 
as we find in Smilacina. 
Luoyp, in discussing the nature of the first four nuclei of the 
embryo sac of the lily, is in favor of calling them spores. “But 
after all,” he says, “spores in the sense meant here are equivalent 
to vegetative cells of a somewhat special sort, with no necessarily 
separate existence teleologically speaking.” He urges against the 
idea that in the lilies the gametophyte begins with the mother cell 
this: “It would seem more natural to regard the gametophyte as an 
individual by coalescence, having its origin in four like vegetative 
cells whose primitive function has been lost.” 
In Pandanus Artocarpus and P. odoratissimus, according to 
CAMPBELL (4), the mother cell develops directly into the 14-nucleate 
embryo sac. The two outer nuclei formed by the reduction divisions 
do not divide, while the two inner nuclei divide to form twelve nuclei. 
A differentiation of the antipodal cells was reported, but no certain 
evidence of nuclear fusions to form the endosperm nucleus was found. 
In 1907 Porscu (20) proposed the theory that the two cell groups 
in the opposite ends of the angiosperm embryo sac are both to be in- 
terpreted as archegonia. The synergids are thought to correspond to 
two neck canal cells, and the upper polar nucleus to the ventral 
canal cell of the archegonium. According to this theory the embryo 
sac of Helosis consists of only one archegonium, the other having been 
Suppressed. The behavior of Smilacina stellata perhaps supports 
is theory, in so far as it shows the equivalent origin of the two groups 
of nuclei which Porscu interprets as archegonia. 
Miss Pace. (19) has reported that Cypripedium forms a iota 
celled embryo sac by two divisions of the lower of two “megaspores- 
This embryo sac may be interpreted by Porscu’s theory to bea single 
archegonium. é | 
Went (28), in a recent article on the Podostemaceae, reports that 
