36 M. Miiller on the Development of the Lycopodiacese. 



of two outer leaves, which are so closely united that they may be 

 said to fit one another like the two hollow hemispheres of a bul- 

 let-mould (fig. 3 a, where they are separated to some extent by 

 slight pressure between two glass plates) . I distinguish them by 

 the name of " bud-envelopes " {Knospenhullbldtter-), because the 

 two inner bodies which they inclose are already in fact two buds, 

 in which may be found the types of the complete organs of the 

 future branches. They are therefore two buds of ramification 

 {Astknospen). A vessel in course of development proceeds toward 

 each of them from the point of vegetation of the stem (PI. II. 

 fig. 4 c). 



Since however all the organs have already been contempora- 

 neously produced in the youngest condition in which it becomes 

 visible to us, I prefer to describe them in a somewhat more ad- 

 vanced stage of development, because at their first production 

 the individual organs are too minute, to allow of our giving a 

 sufiiciently clear representation of them, since it is scarcely pos- 

 sible to prepare them for examination. 



a. The hud-envelopes. They are broad, somewhat oval, almost 

 roundish and having transparent denticulations on the borders, 

 in other parts of a green colour, and in all these characters quite 

 indistinguishable from the leaves of the branches which succeed. 

 They possess but one character which does not and indeed can- 

 not belong to the leaves of the branches. They possess, namely 

 at their base, which, broader than that of the branch leaves, half 

 embraces the stem, a thin, membranous, transparent, cellular 

 membrane, which also half incloses the stem, and usually appears 

 as if torn more or less regularly at the truncated base. This is 

 not organically connected with the stem, but only an appendage 

 to the "bud-envelopes" (figs. 5 — 7). 



I regard this appendicular membrane as a remnant of the in- 

 ternal spore-membrane. For this does not become detached from 

 the terminal bud until after a considerable period, and then re- 

 mains with its upper portion (on which, as I have already said, 

 the primary cells of the " germ " are so closely applied that they 

 grow together with it) also further organically connected with the 

 base of the " bud-envelopes," until the developing stem in the 

 course of its elongation tears through the spore-membrane, ex- 

 actly like the calyptra and vagina of the Mosses, where, as here, 

 the lower portion remains attached to the base of the axis, while 

 the superior portion is carried upwards. This explanation is con- 

 firmed by the fact that this membrane always looks as if it had 

 been torn, and the other portion of the spore-membrane is still 

 to be observed upon the base of the young stem (fig. 5). It is 

 however cellular, while the remaining portion of the spore-mem- 

 brane consists of a homogeneous membrane, and this appears to 



