Note. 
607 
of preservation (Figs. A and B, e.s). The morphology of this part of the sporeling 
presents some difficulty. Having only a single specimen we are without data of 
development, and not even could the position of the archegonium neck be dis- 
covered, since one or two sections of the microtomed series were unfortunately 
lost. Two alternative views are possible. The tuberous body may be either a local 
swelling in the hypobasal region of the embryo, comparable with the foot found in an 
embryo of the Z. cldvatum type, or it may have arisen in the epibasal part of the 
embryo, and therefore correspond with the protocorm of Z. cernuum . In the speci- 
men examined there is nothing against regarding the swollen part of the sporeling as 
a foot, except the fact that it is partly extraprothallial, and even this might be due to 
decay and shrinkage in the gametophyte. On the other hand, the account given by 
Professor Thomas seems to support the second alternative. This observer states 
that the early stages of embryogeny in Phylloglossum are much like those in Z. 
cernuum , and he describes a condition in which the embryo, ‘ a short cylindrical body, 
bluntly pointed at both ends is attached to the prothallus by a foot which is lateral 
in position. It is possible, therefore, that in the specimen described above, a foot, 
relatively small and lateral to the sporeling, was present in the sections which were 
lost. If this be so the bulky mass of tissue half buried in the prothallus must corre- 
spond, not with the foot of Z. clavatum , but with the protocorm of Z. cernuum. It 
differs from this organ, however, in possessing no rhizoids and no endophytic fungus, 
and in being only partially free from the prothallus . 1 
Although the morphology of the embryonic swelling must be left an open ques- 
tion until further observations can be made, the specimen seemed worthy of record 
because the sporeling is found to possess both an embryonic swelling and a charac- 
teristic storage tuber. Thus it demonstrates (<2) that Phylloglossum falls into line 
with one or other of the Lycopodian series with an embryonic swelling, and ( h ) that 
the annual storage tuber is of entirely independent origin. 
1 For discussion of the problem see Bower, Origin of a Land Flora, chap, xxvi, where also 
further references to the literature on the subject are given. I regret that all reference to Professor 
Bower’s treatise was omitted by mistake in my paper on the Morphology of Phylloglossum , Ann. of 
Bot., vol. xxx, p. 315. 
K. SAMPSON. 
Royal Holloway College, 
Englefield Green, Surrey. 
