36 COMPARATIVE EMBRYOLOGY OF THE RUBIACEAE 
very rapidly, and, as indicated in fig. 74, the histolysis is not con- 
fined to the immediate vicinity of the endosperm. In the same 
figure we may note the antipodal cells to be still present, but they 
are in a dead condition, and it would not appear that they are in 
any way active agents in the action described, but rather that the 
enzyme which we may believe is secreted by the endosperm more 
readily passes along the course of the antipodal apparatus and is 
thus distributed to a distance from the endosperm. 
That the behavior of the integument as the endosperm grows 
is indeed the result of the action of an enzyme, we have evidence 
in the case shown in fg. 15, where the cell-walls of the cells 
lining the micropyle remain unaffected, although the surrounding 
tissue has been totally destroyed. 
It is to be noted also that the endosperm nucleus takes its 
position against the egg cell, although this does not appear to be: 
the case in G. finctorum. This may be due to the interference of 
the large and numerous starch grains which crowd the cell and 
would very naturally interfere with the movements of the endo- 
sperm nucleus (fig. 70). 
The food mass derived from the disintegrating megaspores 
becomes exhausted at the maturity of the embryo-sac or soon after 
and no trace of this may be seen soon after fertilization. At this 
time, too, the fertilized egg loses its vacuole by the increase of 
the cytoplasm, and the synergids at the same time disintegrate. 
The course of development of the embryo is, in the early stages, 
like that in the others previously described. 
Asperula 
(PLATES 8 AND 9) 
Of this genus the following five species have been studied: A. 
azurea, galindes, montana, setosa, and tinctoria. 
The “development of the ovule and the appearances presented 
by the archesporium in the genus Asperula do not differ in general 
from the other Ga/ieae. They present, nevertheless, some striking 
points of contrast, especially when compared with Crucianella. 
The early stages of development of the ovule may be passed 
over without further remark. When the definitive condition of 
the archesporium has been attained, the further development of 
