No. 457.] EMBRYO OF THE ANGIOSPERMS 27 
The embryos of the so-called anomalous dicotyledons can as 
readily be interpreted as demonstrating the bifurcation of one 
cotyledon as proving the fusion of two, and if we take into 
account the course of events in their ontogeny they support the 
former hypothesis in preference to the latter. 
While, as mentioned above, some few dicotyledons show a ten- 
dency to reduce the cotyledons there is an opposite tendency far 
more prevalent among dicotyledons to produce lobed, bifid and 
bipartite cotyledons ; undeniably a process of splitting. 
Finally if the foliar-theory of cotyledons can be established 
the writer's entire hypothesis must fall. If the adverse hypoth- 
eses are to be proven, the foliar-theory must first be established. 
THE PHYLOGENY OF THE COTYLEDON. 
In a paper now in preparation, the writer will endeavor to 
demonstrate the validity of his hypothesis concerning the phy- 
logeny of the cotyledon. A previous paper (:02) on this sub- 
ject only served to indicate in an indefinite way the scope of the 
theory. Since that time continued investigations in the field, 
laboratory and library have yielded evidence which bears out to 
a remarkable degree the fundamental idea, at the same time fur- 
nishing the necessary details for a more exact formulation of the 
hypothesis. The following outline illustrates the application of 
this hypothesis to plant embryology. 
Cryptogamic embryos.— The first regional differentiation of 
the body-tissue.of the sporophyte was into the spore-containing 
capsule and the bulbous nursing-foot ; the function of the former 
being the bearing and protection of the spores, that of the latter 
the absorption of nourishment and the furnishing of mechanical 
support. Since these two regions form the bases for all later 
elaboration of the sporophyte we may conveniently assign to 
them the distinctive names of sporophore and haustrum. As the 
haustrum and sporophore are not always distinguishable from the 
first in the embryo we will find the term protocorm! quite ser- 
1 This admirable term was-first used by Treub (88) to designate the * embry- 
onic tubercules ” of various lycopods. The writer simply extends the use of the 
term without seriously altering its original meaning. 
