Frey—Physiology of Venturia Inequalis. 
321 
Bachman (1912-13) finds that the archicarp and spermatia of 
Collema pulposum function. The trichogyne grows toward the 
spermatia, coils about it and fertilization is accomplished. 
Fraser (1913) describes the trichogyne of Lachnea creta. She 
holds that this form is apogamous, no antheridium having been 
found. 
Nienburg (1914) opposes the views of Blackman and Welsford 
on Poly stigma ruhrum. He states that the archicarp has a coil at 
its base and a chain of long multinucleate cells forming a tricho¬ 
gyne. A long multinucleate cell, the antheridium, applied itself 
to the long uninucleate cell, the ascogonium, the walls dissolve and 
the nuclei migrate into the ascogonium where one increases in size 
and becomes the male nucleus. When this male nucleus is equal 
to the female nucleus in size the remaining cells of the archicarp 
have degenerated. The ascogenous hyphae arise from the ascogo¬ 
nium and contain paired nuclei but the development of the aseus 
could not be followed. The trichogyne is not a sexual organ, but 
may be regarded as a vegetative or nutritive structure. Nienburg 
did not observe fusion in the ascogonium or in the ascogenous 
hyphae and believes the only fusion that takes place is in the ascus. 
Brooks (1910) described the development of Gnomonia erythros- 
toma. He finds spermatia are produced but they no longer func¬ 
tion. Several hyphae entwine and a perithecium is formed. Later 
a trichogyne appears. A coil of deeply staining cells forms the 
ascogonium which, however, degenerates. The ascogenous hyphae 
arise de novo, probably from the vegetative hyphae. The only 
nuclear fusion takes place in the ascus. Eeduction occurs in the 
first division 
Moreau (1919) working with Pelligeracees could find no sperma¬ 
tia which possessed the power to function as male cells. The 
ascogonium is multinucleate and no connection between the 
spermatia and the ascogonium was observed. The fusion in the 
ascus is the only nuclear fusion taking place. 
Investigations of the development of Pyronema confluens were 
made by Brown (1915). He states that the form he studied pro¬ 
duces a trichogyne which, however, does not fuse with the antheri¬ 
dium. He observed no fusion of nuclei in the ascogonium or in the 
ascogenous hyphae. The only fusion is in the ascus. 
Welsford (1915) states that the reason paired nuclei are found 
in the ascogonium and ascogenous hyphae is due to better nutri¬ 
tion which causes rapid division. Nuclei in cells filled with large 
