37 1 
Reply to Criticisms. 
gametophytes of these two genera are exposed : they both 
grow in a humid atmosphere, while moist humus, commonly 
in the form of effete and decaying superficial tissues of tree- 
trunks, suits them both : neither the Hymenophyllaceae nor 
the Buxbaumiae can be considered entirely free from the 
charge of saprophytic nourishment (see Haberlandt, loc. cit. 
p. 482). I have elsewhere discussed this question of the 
similarity of the moss-protonema and the prothallus of 
Trichomanes at some length 1 : the main point is that the 
similarity depends on the vegetative organs , such as the 
filamentous protonema-like growth, and the small archegonio- 
phore. But, though there is certainly some similarity of 
their antheridia, the archegonium of Trichomanes or of 
Hymenophyllum is a true fern-archegonium, as regards its 
segmentation and mature structure ; and in point of its single 
neck-cell it is even less like a moss-archegonium than are those 
of certain other Vascular Cryptogams. The archegonium 
of Buxbaumia appears, however, to be a true moss-arche- 
gonium 2 . To me the dissimilarity of the archegonia of 
Trichomanes and of Buxbaumia , as regards form and segmen- 
tation, appears a more weighty fact than the similarity in 
vegetative conformation of the gametophyte, since the arche- 
gonium in ferns and mosses is relatively constant in its 
characters, while their vegetative conformation is not constant. 
When to this is added the suspicion of saprophytism, as well 
as the entire dissimilarity of the sporophyte in Buxbaumia 
and Trichomanes , the case against Professor Goebel’s com- 
parison appears to me to be a very strong one. In the light 
of the new facts contributed by Professor Goebel relating to 
Buxbaumia , I see no reason to alter the opinion set forth in 
my papers above quoted — viz. that such similarity of the 
gametophyte as is found in the mosses and Hymeno- 
phyllaceae, as regards their vegetative development, is 
probably the result of relatively recent adaptation, of one or 
1 Annals of Botany, vol. v. p. 109, &c. 
2 See Goebel’s Figs. 12, 17, PI. VIII, Flora, 1892; also Bruch, Bryologia 
Europaea, iv. PI. I, Fig. 12. 
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