190 DopcGE: METHODS OF CULTURE OF ASCOBOLACEAE 
There are also forms in which the thallus is very poorly de- 
veloped. Some species resemble quite closely species of Humaria 
and Ascobolus which grow on the ground among mosses and algae. 
An investigation of these forms may lead to the discovery of 
initial organs, which will even more convincingly establish the rela- 
tionship between the Discomycetes and the discomycetous lichens. 
I have shown that Ascobolus carbonarius, with its long trich- 
ogyne coming to wind about an antheridial conidium, is suggestive 
of a relationship between this species and the lichens. The 
development of the archicarp directly from a female conidium may 
be an adaptive feature correlated with the commonly occurring 
failure of the rudimentary coils (described p. 175) to develop 
ascocarps. No other ascomycete is known in which the archi- 
carp originates directly from the germination of a conidium. 
I believe, however, that further investigation will show that this 
habit is not confined to this one species alone. When it is cor 
sidered that only a few species of the Discomycetes have been 
cultivated artificially in such a way as to enable the investigator 
to follow the development of the apothecium directly from the 
mycelium, it is not surprising that our knowledge in this connection 
is very limited. 
The multicellular trichogyne of Lachnea stercorea indicates 
phylogenetic relationship between this species and Ascobolus — 
carbonarius. Miss Fraser was unable to trace the origin of the 
antheridium with which this trichogyne fuses. 
There is an undoubted tendency to the disappearance of 
the trichogyne in the Ascomycetes, though this does not necess* 
rily mean a disappearance of sexual reproduction. We can trace 
the reduction of a trichogyne through well graded stages. Wel 
developed septate trichogynes are also found in Ascophanws 
carneus, A. ochraceus, Ascobolus immersus, and A. Wintert. me 
the last two species the trichogyne is not always distinctly dif- 
ferentiated from the ascogonium. Spirally coiled ar chicarp® 
tapering gradually toward the tip, are known in such forms 4 
Aspergillus, Sordaria, Hypocopra, and Saccobolus. Ao 
In Pyronema the archicarp has become reduced to such 4% : 
extent that septa are no longer found in the trichogyn® The 
antheridium has come to be developed sufficiently ne at 
4 
