44 COMPARATIVE EMBRYOLOGY OF THE RUBIACEAE 
After fertilization the endosperm grows very rapidly, and gets 
a large bulk. Although the growth of the embryo is immediate, 
and as rapid at least as in the other plants so far described, it is 
proportionately slower, so that in a fruit so large that one would 
naturally expect to find a large embryo, one finds, on the con- 
trary, a young embryo without cotyledons. The endosperm has 
large cells and contains a very small proportion of plasma. For 
this reason the endosperm plasmolyzes very easily. 
The suspensor of this form is very fully developed (fig. 6). 
The cell divisions are, at first, solely transverse. Soon, however, 
they become irregular and often strictly longitudinal, while all of 
the suspensor cells excepting a few disc-shaped cells near the 
embryo proper, and still fewer at the micropylar end of the sus- 
pensor develop into haustoria. The relatively greatest develop- 
ment is reached by the suspensor when the embryo proper has 
about eight to sixteen cells. The pressure exerted by the endo- 
sperm upon the suspensor, together with the direction of growth 
of the same causes the suspensor to be drawn out, so that the 
embryo proper appears to be anchored to the endosperm, which 
in this way is enabled to exert a tension upon the suspensor. 
Crucianella 
(PLATE 10, FIGURES 7-22) 
Of the genus Crucianella, three species, namely, ۰ gilanica, E 
macrostachya, and C. herbacea have been studied. These present 
certain anomalies which are of not a little interest in view of the 
close relationship between Crucianella and the rest of the Galicae. 
The archesporium consists of 12 to 15 very large embryo-sac- 
mother-cells, which, however, vary between themselves in size. 
The largest occupy the more central position, and these are also 
distinguished by the completeness of their nuclear divisions ; the 
other cells divide less regularly or not at all, and the more quickly 
show signs of degeneration. The cell walls between the mother- 
cells are very delicate, but are present and easily distinguishable. 
The division of the megaspore mother-cells each into four 
£ PREND 
BOREAS i = 3 
IPG AV A ne O A 
grand-daughter cells is remarkably regular, and results in the E 
formation of four megaspores which are alike in size, but not 
separated by cell walls. This feature, to which only very occa- ， 
