824 M. Miiller on the Development of the Lycopodiacese. 



9. The oophoridium in Selaginella denticulata, and all those Se- 

 laginellae where it stands at the base of the spike, is always a meta- 

 morphosed main-branch. This is the case in Selag. ferruminata, 

 Sprg. (= elongata, Klotzsch), lucidinervia, Sprg. [= pedata, Kl.), 

 conduplicata, ej., distorta, ej., Poppigiana, ej., sulcata, ej., stolo- 

 nifera, ej., deliquescens, ej., puberula, Kl., Icevigaia, Sprg., arti- 

 culata, &c. Whether this law may be modified in those species 

 where antheridia and oophoridia occur on one spike, whether it is 

 here a transformed secondary branch, e. g. in ^. stellata, Sprg., 

 pygmaea, ej., helvetica, ej., &c., yet remains to be investigated. In 

 other Selaginell(je, the fruit of which is dioecious, where therefore 

 oophoridia and antheridia occur on distinct spikes, the oopho- 

 ridium appears to be a metamorphosed main-branch, e. g. in 

 S. selaginoides — certain it is however that the oophoridium is 

 never a leaf- product. 



The oophoridium-spores, more proper-ly the ovules, are formed at 

 the extremity of the vascular bundle which projects free into the in- 

 terior of the oophoridiuin as a hollow mother-cell. The course of 

 its development still requires to be more minutely investigated. 



10. The antheridium is a metamorphosed twig-bud* [Zweig- 

 knospe) developed simultaneously with the leaves from the axis, a 

 twig here being understood to be a secondary branch. The an- 

 theridium is never a leaf-product. Here refer also the sporangium 

 of Psilotum and Tmesipteris. 



The antheridium-spores originate by fours in a mother-cell, and 

 certainly by cytoblast-formation as understood by Schleiden (for- 

 mation of a membrane around a nucleus), never by division of 

 the cytoblastema. 



EXPLANATION OF PLATES IL to VL 



Plate IL 



Fig, 1. The germinating spore: a, the rootlet; &, the terminal hud ; c, the 



germ. 250 \. 

 Fig. 2. The terminal hud so seen that the other hranch-hud lies behind the 



one a. 250. 

 Fig. 3. The same, unfolded artificially. 250. 

 Fig. 4. The whole germinating plant, removed from the spore : a, the point 



of vegetation for the stem and root ; h, the germ (Keim-korper). 50. 

 Fig. 5. The germinating plant with the bud-leaves. 10. 

 Fig. 6. A bud-enveloping leaf, with a branch-bud a; 6, an accessory organ. 



250. 

 Fig. 7. The base of the bud-envelope. 400. 



• The word ZweigJcnospe, literally twig-bud, is here used in distinction to 

 AstTcnospe or branch-hud, which latter may be regarded as determining the 

 bifurcation of the main axis, while the former is a secondary ramifica- 

 tion. — Tr. 



t The figures give the magnifying power. 



