164 DopGE: RELATIONSHIPS OF FLORIDEAE AND ASCOMYCETES 
nema. Miss Bachmann finds that the spermatia of C. pulposum 
are not borne in spermogonia as they are in the forms described 
by Stahl and others, but are borne singly or in small numbers on 
branches from the vegetative hyphae imbedded deeply in the 
thallus (Fics. 1,C, and 3, D). These spermatia never find their 
way to the surface of the thallus and commonly remain loosely 
attached to the spermatiophores. The general character of the 
fertile branch is not unlike that of other Collemas (Fic. 1, A and 
B) except as to the structure of the trichogyne and its behavior 
‘in fertilization. The specific attraction which the spermatia 
have for the trichogyne is positively proved by the fact that the 
trichogyne does not bore outward to the surface of the thallus 
but is compelled to wind in and out among the vegetative hyphae 
and colonies of algae in order to connect with the spermatia isolated 
within the thallus. Several trichogynes may be found growing 
towards the same cluster of spermatia. The somewhat swollen 
receptive cell of the trichogyne of the lichens heretofore described 
(Fic. 1, A) is well adapted for its purpose. Extensive surface 
area and stability are provided by its increased diameter. In 
Collema pulposum, by virtue of the certainty with which the tip 
is directed toward the spermatia, no such provision is necessary. 
However, the receptive surface here is probably much increased 
by the great elongation of the end cell, which in some cases occu- 
pies over one half the entire length of the trichogyne. Wolff 
(94) describes the end cell of the trichogyne in Graphis elegans as 
being extremely long. In fact no septa were found in the vertical 
portion of the trichogyne. | 
The trichogyne of Lachnea stercorea (Fic. 2, B) described by 
Miss Fraser (45) represents another type intermediate between 
those of Pyronema and Collema. It is a thick five- or six-celled 
outgrowth of the odgonium and curves downward fusing with a 
long irregular club-shaped cell which Miss Fraser believes is an 
antheridium. 
The trichogynes in the lichens, Ascobolus carbonarius, and 
Lachnea stercorea are quite as strongly developed as the corre 
sponding organs in the red algae. The land habit has, however 
led to their reduction and even disappearance in many forms of 
Ascomycetes. 
