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W. C. Worsdell. 
primary root present; but from the base of the elongated hypocotyl 
two to three short rhizophores develop, and it is indirectly and 
endogenously from these that the first roots arise. Goebel compares 
this “ outgrowth,” as he calls it, from the hypocotyl with the 
“ protocorm ” of the seedling Lycopodium. 
In Lycopodium, indeed, the morphology of the seedling is not 
at all dissimilar to that of Selaginella ; the hypocotyl is, however, 
reduced to a minimum and developes at once into the “protocorm,” 
a tubercle-like body bearing rhizoids. It is only at a subsequent 
period that the first root is formed endogenously or exogenously 
from the “protocorm.” From the above facts it seems to me highly 
probable that the rhizophore of Selaginella and the so-called 
“ protocorm ” of Lycopodium are homologous structures; and if, as 
I am quite convinced, the rhizophore is morphologically a modified 
shoot, then it follows that the “ protocorm ” is also a highly modified 
shoot; and there is nothing on a priori grounds to render this 
conclusion improbable. 
Now Lang found that in the saprophytic species of Lycopodium, 
e.g., L. clavatum, the “ protocorm ” is absent and the primary root 
developes directly from the base of the hypocotyl. He states that 
the type of L. cernuum, with large prothallus and well-developed 
“protocorm,” is the primitive type. In L. Phlegmaria, only a 
degree less primitive, the protocorm is only just distinguishable. 
Hence I conclude that in the saprophytic forms the “ protocorm ” 
has merely been reduced to a vanishing point, just as the hypocotyl also, 
as compared with that in Selaginella, has practically gone. Neverthe- 
less, the basal part of the young plant must be homologized with a 
“protocorm” out of which the root grows. Bruchmann’s investigations 
of seedlings of Selaginella shew that Pfeffer, Campbell, Velenovsky 
and others are mistaken in supposing that a primary root is present 
at all in this genus ; Velenovsky figures seedlings of 5. pumila and 
S. Preissiana in which the primary root, according to his account, 
has arisen endogenously from the hypocotyl, which seems to indicate 
that the extreme basal portion of that organ is, in reality, a rhizo¬ 
phore, which has, like the “ protocorm ” in certain Lycopodiums, 
almost reached its vanishing point. 
It is in Phylloglossum that the “ protocorm ” reaches its best 
development. 
By keeping a shoot of S. Mettenii in a moist atmosphere I was 
able to induce normal rhizophore-formation in the upper part which 
usually produces leafy shoots in place of rhizophores (i.e., in the 
