1922] DUFF—GEOGLOSSACEAE 287 
In Icmadophila the procarps are slightly if at all reduced, in Sphyrid- 
tum they have lost the trichogyne and become somewhat irregular 
in form, while in Baeomyces it is questionable whether such struc- 
' tures can be said to occur at all. Among the Geoglossaceae we 
have Cudonia illustrating a condition entirely comparable with that 
of Icmadophila, while Spathularia resembles Sphyridium in the 
much-reduced nature of its procarps. In Trichoglossum the sex 
organs do not stand out as morphologically distinct structures. 
That these stages in reduction give a picture of the direction of 
evolution of sexuality in both groups is the opinion of the writer. 
Beginning with a form of procarp in which a true process of ferti- 
lization through the medium of the trichogyne took place, the evolu- 
tion of these plants seems to have been marked by the successive 
suppression of the male organ, the trichogyne, and finally the pro- 
carp as a distinctive morphological body. 
The facts observed in the Geoglossaceous forms examined point 
in a contrary direction to the opinion held by BLackmMaN and 
WELSFoRD (1), as stated in their paper on Polystigma rubrum. 
They maintain that in all cases where a degenerate ascogonium 
occurs, the ascogenous hyphae will probably be found to originate 
independently of this organ. Their own recorded observation that 
e well organized procarp of Polystigma rubrum takes no part 
whatever in the formation of ascogenous hyphae lacks confirma- 
tion. Indeed, NIeNBURG (19), in a more recent work on this 
species, maintains that ascogenous hyphae do originate in the pro- 
carp. Brooks’s (2) similar contention with regard to the part 
played by the procarp of Gnomonia erythrostoma, and Fiscu’s (13) 
statement on Woronin’s hypha in Xylaria polymorpha, are offset by 
H. B. Brown’s (3) observation that the cells of the Woronin hypha 
of X. tentaculata actually do become ascogenic. 
The parallelism shown to exist between Geoglossaceous and - 
disco-lichen forms must surely be significant of phylogenetic 
relationship. The question of the relationship of these groups is 
of practical interest, in view of the conviction on the part of certain 
botanists that the lichen genera should be distributed among those 
of the fungi proper. It is recognized by many who favor such a 
procedure that the history of the reproductive tracts must ulti- 
