118 M. Miiller on the Development of the Lycopodiacere. 



further examined hereafter. Finally, the view becomes incon- 

 trovertible from an anomaly which I have observed once, where 

 both the branches of the fruit-bearing axis had been transformed 

 into oophoridia. Here of course the spikelet was wanting, and 

 two oophoridia were opposed to each other, the most complete 

 proof that the terminal bud of that branch had been transformed 

 into an oophoridium, which properly should have produced a 

 branch. 



It would be very interesting to trace the formation of the 

 oophoridia in a fruit-axis which bears these organs alone, as in 

 L. selaginoides. Here the axis of the branch is very slender, as 

 in L. denticulatum, but the formation of the oophoridia, which 

 takes place within a spike, is distinct. This is explained, as we 

 have already seen, only by the thickness of the fruit-axis, as this 

 increases in thickness as it proceeds upwards, and does not branch 

 beyond like the inferior portion of the axis of the branch. This 

 ramification however occurs again above in a more evident de- 

 gree, since the individual joints of the axis become so distinctly 

 shortened that the stalk of the spikes becomes diverted outwards. 

 Here also there is no doubt that the oophoridium is a metamor- 

 phosed branch, and a history of the development of this most 

 interesting species is very desirable. 



Consequently the view of H. Mohl and Schleiden in reference 

 to the oophoridium, that this sporangium is a production from 

 the leaf, is certainly incorrect ; neither is it formed of carpellary 

 leaves, as Bischoff endeavoured to show. 



b. The formation of spores. A new question to which I now 

 come relates to the formation of the four germinative spores in 

 the interior of the oophoridium. I regret that I cannot offer a 

 perfect account of their development. What my researches have 

 hitherto made me acquainted with on this point is limited to the 

 following. 



If we cut through the oophoridium in the direction of its 

 length in a very young condition, the view of the interior con- 

 firms what we have above concluded from its external conforma- 

 tion. The membrane of the oophoridium is a mere development 

 of the apex of the axis and is identical with the epidermis of the 

 leaf, both being formed by the outermost cellular layer of the 

 axis (figs. 7, 8). It is only at a subsequent period that the leaf 

 acquires an organ, the porous slit, which never shows itself in 

 the oophoridium. The membrane of the oophoridium is not 

 equally strong at all points, but much thickened at the vertex 

 (fig. 7 a). It is also decurved somewhat over its point of attach- 

 ment, the future pedicel (fig. 7 b), whence this latter comes to 

 be situated in a longitudinal fold which is continuous with the 



