1912] PFEIFFER—LEITNERIA 199 
considered a group character. Again, the extent of tissue devel- 
opment in the nucellar region is so variable a character that one 
finds reports of deeply placed embryo sacs, such as are found in 
Leitneria, reported in Casuarina (7, 8), in Triticum (9), in Cuphaea 
(10), and in other entirely unrelated forms. 
Another character which Letineria has in common with the 
majority of Archichlamydeae is the initiation of the development 
of the embryo sac by a megaspore rather than by a megaspore 
mother cell, so that while a tetrad of spores is formed, a single 
megaspore functions. In the embryo sac that develops from this 
megaspore the synergids are characterized by being full of cyto- 
plasm, rather than by having the large, distinct vacuole, as often 
found in the antipodal end of the cell. This, while a character not 
often reported for the synergids of forms even where the synergids 
are relatively small, is of course not a character which would hold 
any weight taxonomically. The ephemeral antipodals are found 
in many forms, as in the Salicaceae and Cupuliferae. 
After fertilization, the behavior of the endosperm nucleus and 
of the fertilized egg is in no way extraordinary; while extreme in 
some cases, as in the great development of free nuclei of the endo- 
sperm before the division of the fertilized egg occurs, still there is 
no character of first importance which would indicate relationship 
with one family or another. Thus the more or less extensive 
development of free endosperm nuclei before the segmentation of 
the egg is a character shared by Piper (11) and Asclepias (12). 
The very regular centripetal growth of endosperm tissue after walls 
appear is extreme, and is rarely found so well developed in angio- 
spermous seeds. The most striking character of the embryo itself 
is the massive suspensor. But this character, too, is shared by 
most of those forms, such a Peperomia pellucida (13), in which the 
first division of the fertilized egg may be longitudinal rather than 
transverse. It is of interest to find here again a form in which 
there is no fixed sequence of cell divisions in the development of 
the embryo, such as have long been emphasized in such forms as 
Capsella. 
One might go on indefinitely pointing out some particular in 
which Leitneria resembles one or the other of the Archichlamydeae, 
