452 Mot tier . — The Embryology of some Anomalous Dicotyledons . 
manner as Fig. 6 , from an embryo of a mature seed. The sinuses are of 
unequal depth, the primary cleft being deeper. There is no protruding 
stem- apex or plumule. The cotyledons are crescentic in cross-section, 
being concave on the inner surfaces. There is no cotyledonary tube formed 
in Actea alba . Although the cotyledons have a common base, yet they 
cannot, as will be shown in the following paragraph, be regarded as one 
cotyledon which has bifurcated. Such an interpretation might be defensible 
if all embryos of Actea alba followed closely the line of development as 
detailed in the foregoing. 
It will now be shown that there is in this species what may be reasonably 
regarded as typical dicotyledonous development. Instances were found in 
which the cotyledonary sinuses appear at about the same time. Fig. 18, a-h , 
represents in outline a series of transverse sections, beginning just below 
the base of the cotyledons. Of course it cannot be stated with absolute 
certainty that the cotyledonary primordium was not slightly crescentic in 
its earliest stage, but from younger stages of a similar condition, and from 
the evidence obtained in Syiidesmon , to be mentioned below, it is highly 
probable that the primordia of the cotyledons were separate or nearly so. 
As in the former case, it will be seen from b, Fig. 18, that the origin of the 
cotyledons involves almost the whole truncated end of the embryo. Fig. 
1 6, which is b, Fig. 18, drawn in detail, shows the same condition of things 
as indicated in Fig. 14. Fig. 16, b , is taken at a level corresponding with 
that of Fig. 14. In Fig. 18 is shown what is of frequent occurrence, 
namely, the unequal length of the two cotyledons. In several cases 
examined, both in Actea and in the other species to be mentioned later, 
the two cotyledons are not only of unequal length, but one may be more 
massive as well. Cases are also met with in which the embryo was 
obliquely symmetrical (Fig. 15). It may be mentioned further that, in ripe 
seeds of the same ovary, the embryos are frequently of different sizes, and 
may have attained appreciably different stages in development. 
Sanguinaria canadensis. 
The earliest stage observed in the development of the embryo of 
Sanguinaria canadensis is shown in Fig. 9, which is a median longitudinal 
section. At this stage the embryo is cylindrical, as shown in cross-section 
(Fig. 10), with a very short suspensor of about two or three cells. The 
cytoplasmic contents of the cells are regular and uniform, little or no starch 
being found in the embryo at this or later stages. The resemblance of this 
embryo to that of Monocotyledons in similar stages of development is 
noticeable, but no special significance can be attached to this fact. As has 
been pointed out in Actea alba, the immediate subsequent development 
results in a pear-shaped structure (Fig. 20, an outline of a median longi- 
tudinal section). As this figure indicates, the suspensor is short, merging 
