132 BOTANICAL GAZETTE [FEBRUARY 
JEFFERSONIA DIPHYLLA. 
The development of the embryo sac of Jeffersonia has been 
described by Andrews (1895). The mature embryo sac differs 
from the typical form only in the large size of the antipodal cells. 
The fecundated egg cell elongates and is divided into two cells by 
a transverse wall (fig.z75). The embryo soon elongates, the distal 
end becomes somewhat broadened, and a definite suspensor con- 
sisting of two or three cells is formed. The cells at the distal 
end are divided by longitudinal walls, but the suspensor remains 
as a single row of cells (figs. 76,77, 78). In fig. 15a synergid 
is shown which has increased greatly in size. This is an unusual 
occurrence, as the synergids usually disappear early. By the 
time the embryo has reached the eight-celled stage a large num- 
ber of endosperm nuclei can be seen scattered about in the cyto 
plasm of the embryo sac. The antipodal cells disappear veTy 
early. 
The suspensor increases in length by the growth and division 
of the cells composing it. The cells divide by transverse walls 
until a row of four or five cells is formed. At first the body of 
the embryo seems to increase in size by the division of its cells 
in three planes, so that it becomes rounded ( fig. To}: A little 
later the body elongates, and the symmetrical form shown in fig: 
20 is produced. Growth now takes place most rapidly in a lateral 
direction, the distal end becoming broad and truncate. Fig. 21 
represents a stage just before the beginning of the development 
of the cotyledons. The development of the embryo to this point 
corresponds very closely with that described for Podophyllum. 
The cavity surrounding the embryo is small, and the endosper™ 
cells near it do not become so nearly disorganized as in Podo- 
phyllum or Caulophyllum. 
Examination of longitudinal sections, or of series of cross~ 
sections of embryos in which the cotyledons are somewhat 
developed, would lead one to the conclusion that Jeffersonia is 4 
typical dicotyledon (figs. 22, 23). There is a slight peculiarity 
in the origin of the cotyledons, however, which is shown by 4 
series of cross-sections at the stage when the cotyledonar pri- 
mordium first appears. Fig. 24 shows that the cotyledons really 
