Notes on Recent Literature. 
type of seedling structure in this order becomes of greater importance 
than Miss de Fraine concludes. It is no longer necessary to look upon 
it as accidental. Among the Cactaceae this type of transition occurs, 
as has been already mentioned, in those genera whose seedlings are 
least modified, and it is in such cases that we should naturally 
expect to find that ancestral characters had been retained. It 
would appear that Miss Sargant’s view that the various mono- 
cotyledonous and dicotyledonous types of seedling anatomy were 
all originally derived from the Anemarrhena type, is strengthened, 
rather than weakened, by the discovery of this ancestral type among 
the Cactaceas. 
There is, however, a further question to be considered. How 
far does the view hold good that, in Eranthis , it is the formation of a 
cotyledonary tube that has led to the survival of the ancestral type 
of vascular symmetry? It certainly seems as though Miss de 
Fraine’s discovery of the Anemarrhena type of transition among 
Dicotyledons which do not form a cotyledonary tube, tends to dis¬ 
prove this contention. It may well be a mere coincidence that 
Eranthis possesses a cotyledonary tube, while at the same time it 
has retained the Anemarrhena type of vascular symmetry. In dis¬ 
cussing this problem it is essential to keep two questions apart in 
one’s mind:— 
1. What was the ancestral form of vascular symmetry in 
Angiospermous seedlings ? 
2. If it be conceded that the primitive transition structure was 
of a bisymmetrical type, suggesting a dicotyledonous ancestry,—by 
what method was the change from two cotyledons to one brought 
about ? 
Eranthis happens to supply an answer to each of these questions. 
It has the bisymmetrical vascular system, and indications of a 
tetrarch root, which, it may be held, are ancestral. It also possesses 
fused cotyledons, suggesting a simple way in which one cotyledon 
can replace two without any loss of symmetry. 
As regards seedling study in general, Miss de Fraine closes her 
paper with the following somewhat pessimistic expression :—“ It is 
not justifiable to use the seedling structure as an indicator or 
phylogenetic connexions.” 
Such a statement is difficult to controvert, since no phylogenetic 
criterion can, in the nature of things, be universal and absolute. The 
weight to be attached to seedling structure as a clue to phylogeny 
may be widely different in different families of plants. It is, perhaps, 
unlikely that a group will ever be discovered in which the seedling 
structure gives so clear an indication of affinities as it does in the 
various tribes within the Liliaceae. This is, however, exactly 
parallel with other well-known facts, both among plants and animals. 
Darwin 1 quotes Robert Brown, who says of certain organs in the 
Proteaceae, that their generic importance, “ like that of all their 
parts, not only in this, but, as I apprehend, in every natural family, 
is very unequal, and in some cases seems to be entirely lost.” 
Darwin recalls a similar instance among the Hymenoptera, and 
concludes, “ Any number of instances could be given of the varying 
importance for classification of the same important organ within 
the same group of beings.” 
1 L.c., p. 343. 
