266 Bower . — Imperfect Sporangia in certain 
may not have antedated the whole vegetative system of the 
sporophyte, as the antithetic theory implies : but in any case 
spore-formation was of early date. 
The theory of sterilization of sporophylls above stated for 
Lycopods embodies a tangible idea, which is in accordance 
with the facts, including those relating to abortive parts. It 
was met on a previous occasion by Prof. Goebel, first by 
a reference to large-leaved forms, and especially to his earlier 
observations on the sporophylls of Onoclea ; but without refer- 
ence to the detailed facts for Lycopodium , on which my argu- 
ment was based 1 ; subsequently by a simple ‘non possumus’ ; 
and here again there was no reference to the facts relating to 
Lycopodium 2 ; nevertheless he remarks that ‘ Botany as a 
science is more concerned with facts than with phylogenetic 
theories.’ He concludes, after a reference to Ferns, but still 
ignoring the Lycopods, that ‘ as to what occurred in prehistoric 
ages, we require far more convincing proofs than are afforded 
by the materials at present within our reach, before we can 
speak with any assurance.’ It was met by Dr. Gluck by the 
old assumption 3 , that the ontogeny is a key to the phylogeny : 
that because the foliage leaves are prior in the individual, 
therefore the later-formed sporophylls are altered foliage 
leaves. Readers may then choose between, first, the ‘ non 
possumus 5 position, which declines to entertain any phylo- 
genetic theory on the point in question : I think this will not 
commend itself to inquiring minds, if they give attention to 
the facts which I have brought forward. Secondly, the posi- 
tion which assumes a prior vegetative system of the sporophyte, 
but gives no explanation how or when, in the descent, the 
spore-production, which is so constant a feature at the present 
day, came to be imposed upon it 4 . And thirdly a coherent 
1 Annals of Botany, vi, 1892, p. 359. Also Ber. d. d. Bot. Ges., 1887, p. 69. 
2 Science Progress, iii, p. 120. 3 Sporophyllmetamorphose, p. 383. 
4 Goebel wrote as follows on this point (Ber. d. d. Bot. Ges., p. 74): ‘Die 
Pflanze bildet nur eine Art von Blattanlagen, und zwar Laubblattanlagen, von 
denen aber, infolge bestimmter Einwirk ungen, regelmassig ein Theil zu Nieder- 
blattern, ein Theil zu Sporophyllen sich ausbildet, wahrend die iibrigen sich als 
Laubblatter weiter entwickeln.’ 
