460 Mottier . — The Embryology of some Anomalous Dicotyledons . 
found in certain Nymphaeaceae and Ranunculaceae as a basis, it is easy to 
show how, during phylogeny, this primordium, by a bifurcation opposite 
the primary sinus, might have given rise to two cotyledons. Or if the 
primordium should develop as one piece without undergoing a bifurcation, 
the resulting cotyledon might then be looked upon as a union of two 
cotyledons. The former is the view held by Lyon, the latter, the inter- 
pretation given by Miss Sargant. 
As a matter of fact, the writer believes that the investigations of 
Schmid (’02) on species of Ranunculus and Corydalis, and the results 
of similar studies upon species of the Ranunculaceae and Papaveraceae 
as detailed in the foregoing paragraphs, together with the observations 
of Lewis (’04) on Podophyllum and Jeffersonia , show conclusively that the 
anomalous character of the embryo is not a primitive, but purely a derived 
condition. In the genera forming the basis of this paper, it is seen that 
there is a transition from the anomalous embryo to that which is typically 
dicotyledonous, and that this transition is seen in different species of the 
same genus. Schmid points out that, in Ranunculus Ficaria and Corydalis 
cava> only one cotyledon develops, leaving us to infer that the second is not 
formed, but in both Corydalis nobilis and C. lutea two cotyledons are 
typically formed. Are we to infer, therefore, that Corydalis cava represents 
a primitive condition in the development of its embryo, while C. nobilis and 
C. lutea do not ? Schmid states further that the seedling of C. cava forms 
a tuberous stem, while C. nobilis and C, lutea do not. Cook (’03) has 
shown also that in Claytonia virginica , a geophilous plant, only one cotyle- 
don develops, the other remaining abortive. It is probably true without 
exception that dicotyledonous plants possessing anomalous embryos are 
either partly or wholly geophilous in habit, having stems either in the form 
of a rhizome, tuber, or a short, squat axis. In other words, the anomalous 
character is in all probability correlated with an hypogean habit. There 
can be no doubt, I think, that the cotyledonary tube is merely an adaptation 
to a geophilous habit, as seems to be shown in all plants possessing the 
same. If, on the contrary, the cotyledonary tube and the anomalous embryos 
represent primitive characters, then it must be shown that the geophilous 
habit is a primitive condition, but the writer does not believe that that has 
been done up to the present, at least. If the conclusion arrived at here 
is correct, anomalous Dicotyledons thro whittle or no light upon the relative 
antiquity of the two classes of Angiosperms ; for as embryological evidence 
is of greater value than anatomical, it seems as reasonable to conclude, 
using the anomalous character as a basis, that Dicotyledons have been 
derived from Monocotyledons as the reverse. 
