ioo Hill.—The Structure and Development of 
sac). Other embryo-sacs which showed a multiplication of 
the antipodal cells were quite normal as regards their egg- 
apparatus. Preparations showing the actual divisions of the 
antipodal cells were unfortunately not obtained, so that it is 
impossible to say whether they increase by fragmentation or 
by karyokinesis. 
A considerable amount of time was spent in endeavouring 
to obtain preparations at the time of actual fertilization, in 
order to ascertain whether the same phenomena obtain in 
Triglochin as have been found in Lilium by Nawaschin (12) 
and Guignard ( 7 ). These efforts were unfortunately unsuc¬ 
cessful, and the failure may perhaps be at least partly due to 
the small size of the nuclei concerned. 
The polar nuclei, as far as could be ascertained without 
the actual stage of fertilization of the oosphere having been 
observed, do not appear to fuse till after fertilization, and, 
if this be correct, Triglochin in this respect would differ from 
Spargaiiium simplex , and would resemble 5 . Greenii as 
described by Campbell. 
Examples of the fusion of these polar nuclei are illustrated 
in Figs. 30 and 32, PI. VII. 
Embryology. 
The embryology of Triglochin maritimum in its chief 
features conforms to the type commonly met with amongst 
most Monocotyledons. 
The chief peculiarities which distinguish Triglochin lie in 
the earlier divisions of the oospore. 
The first division of the oospore takes place by means of 
a transverse wall cutting the original cell into a lower basal 
and a terminal embryo-cell (Fig. 34). 
The terminal embryo-cell then divides by another trans¬ 
verse wall, thus giving rise to a three-celled structure (Fig. 35). 
The next division which takes place was not actually ob¬ 
served, only the four-celled embryo which is thus produced 
being seen (Fig. 36), but judging from appearances it seems 
