248 M. Miiller on the Development of the Lycopodiacese. 



more (fig. 14) or less (fig. 13 b) grouped together. At a subse- 

 quent period the absorption of the membrane of the mother-cell 

 takes place. 



The outer membrane of the bean-shaped secondary cells is ex- 

 ceedingly delicate and transparent, almost as clear as glass, and 

 thus they produce a very pleasant impression on the eye. The 

 contents consist at present of the cytoblast : this now undergoes a 

 new series of essential changes, into which I will therefore enter 

 more minutely. 



It either hes upon the wall, or attached upon a mucilaginous 

 mass more in the centre of the cell (fig. 17). The other charac- 

 ters of position are also excessively variable ; sometimes it is in 

 the midst of the cell, sometimes more approached toward the 

 end or in the end itself (figs. 15 — 20). In the stages where the 

 membrane of the mother-cells is undergoing absorption and the 

 secondary cells come to lie free in the sporangium, the cytoblast 

 becomes altered. Its substance is dissolved, and this usually 

 occurs in such a way that its external border remains behind ap- 

 pearing like a mucilaginous membrane (figs. 18 — 20). The cy- 

 toblast often disappears altogether (figs. 21 and 22). 



The mucilaginous fluid originating from the solution of the 

 greater part of the cytoblast passes now into a new structure. 

 It becomes deposited in the shape of exceedingly delicate, minute 

 globules, again coagulated, round the whole internal periphery 

 of the bean-shaped secondary cell or spore, and appears like a 

 very fine precipitate giving the spore a grayish-coloured aspect, 

 produced by the shades the single globules cast around them, 

 whereby of course a peculiar mingling of dark and bright points 

 is necessarily brought about. The outline of the cytoblast is 

 often still to be observed, usually in a roundish form (fig. 23). 

 Before long, the granular contents swell into larger globules 

 which are more or less closely assembled together (figs. 24and25). 

 If, in this condition, the membrane of the spore is cut through, 

 a most distinct conviction may be obtained that the remaining 

 space is empty, and that it is from the granular cell-contents 

 alone that the larger globules have originated. At the same 

 time it is seen that the spore-membrane is simple and apparently 

 tolerably tough. 



Lastly, the termination of the whole formation is a contrac- 

 tion and corrugation of the hard spore-membrane. It also tears 

 in places, and now occurs a very remarkable phsenomenon. 

 The globules (PI. VI. fig. 26), which, when treated with very 

 concentrated tincture of iodine, appear distinctly hollow (fig. 27) 

 and more or less round, begin to elongate into thick filaments 

 (fig. 28). These frequently branch in the most manifold curves 

 with thick prolongations, and thus usually grow through the 



