Embryo in Lilaea subulata , H.B.K. 7 
to be a true dichotomy like that which occurs in Naias 
previous to the formation of the flower. 
In Fig. 3 is shown a median section through the floral complex 
from the middle region of a very young inflorescence. The 
arrangement of the organs suggests very strongly that found 
in Naias at a similar stage of development h This consists 
of two nearly equal superimposed protuberances, respectively 
J and ? , which apparently are formed by a true dichotomy 
of a common primordium. The latter has below it a very 
slightly projecting ridge, /, the rudiment of the subtending 
bract found in the older flowers. Of the two parts into which 
the primordium is divided, the upper is bluntly conical in 
form, the lower more pointed when seen in section, but really 
considerably flattened in the plane of division of the primor- 
dium. The upper prominence is the young carpel, the lower 
the stamen. Each of these structures, from analogy with 
the very similar ones in Naias and Z annichellia, may be con- 
sidered as representing shoots of equal morphological value, 
resulting from the dichotomy of a common primordium. If 
this view is accepted, both the stamen and carpel must be 
considered as truly axial structures. 
The young primordium is composed of nearly similar cells, 
which are arranged in the manner characteristic of the stem- 
apex of the Angiosperms. There is a definite dermatogen 
below which is a pretty clearly defined layer of periblem 
which separates the dermatogen from the central plerome- 
mass. This arrangement is especially clear in the staminal 
rudiment. 
The Male Flower. 
The development of the single stamen which constitutes 
the male flower, whether formed alone in the axil of the 
bract, or secondarily from the dichotomy of the axillary 
primordium, follows the same line of development. 
1 Magnus, Beitrage zur Kenntniss der Gattung Naias; Berlin, 1870. Campbell, 
A Morphological Study of Naias and Zannichellia, Proc. California Academy of 
Sciences, 1897. 
