M. Miiller on the Development of the Lycopodiacese. 323 



The rootlets are not formed till afterwards upon the outside of it. 

 Another proof that the Lycopodia cannot be said to have a main- 

 root. 



4. The terminal bud becomes inclosed by an envelope [two bud- 

 envelopes, Knospenhilllbldttern) . These remind us of the cotyle- 

 dons of the Dicotyledons. At all events those bud-envelopes are 

 identical with it, which so often occur in the Phanerogamia, e. g. 

 in many Leguminosce, as in Amicia, Lathynts, Pisum, in Agri^ 

 monia, in Cunonia capensis, especially, exactly as in Selaginella 

 denticulata, in the Begonias, &c. Here these enveloping leaves 

 have usually been looked upon as stipules. It is impossible that 

 they can be such ; for they are distinguished from true stipules, 

 e. g. in Roses by the fact that they always inclose axial buds, and 

 always surrounding the stem at the origin of the internode, they 

 persist or drop off [Cunonia), while the stipules, mere appendi- 

 cular organs, rest upon the leaves. This is alluded to in another 

 place. 



5. The Selaginellae possess a main-axis. This however remains 

 very short and divides at once in the terminal bud into two 

 branches, which in like manner always divide again dichoto- 

 mously. Hence the '' caulis dichotomo-procumbens.^^ 



6. The leaf is merely an " outshoot " [Auftreibung) of the stem, 

 which expands into a flattened body. 



7. In Selaginella denticulata an accessory organ also is found 

 between the axis and the leaf; the import of this is as yet doubtful. 

 In more recent researches in living Selaginella I found it also in 

 Selaginella stellata, apus and viticulosa, and of exactly the same 

 structure. It thus becomes probable that it extends throughout 

 the whole of the genus Selaginella. 



8. Among the significant peculiarities in Selaginella is also to 

 be included the extremely regular position of the branch-roots. I 

 mentioned above that they are formed upon the upper side of the 

 stem in Selag. denticulata, and that Schleiden, without referring 

 to the species, says that he has observed them on the under side. 

 Since this was printed I have become acquainted with several 

 living Selaginella in the Berlin Botanic Garden, and I found in 

 one of them, in Selag. stellata, Spr., a confirmation of Schleiden^s 

 assertion. I thus had an opportunity to seek for the law which 

 prevails here. It proves to be as follows : the roots of the branches 

 make their appearance both on the upper and under side of the 

 stem, but always just inferior to the forked division of a branch, 

 and indeed within its last leaf. If this be on the upper side — and 

 then it is a folium intermedium — there, also, the branch-root ap- 

 pears. But if the leaf be on the under side — and it is then a larger 

 leaf — the branch-root also is formed on the under side always 

 between the stem and leaf, consequently as a true branch. 



23* 



