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Freda M. Bachmann 
(lescribed and carefully figured by Harper (51) and very recently by 
Claussen (20), is thought to liave a non-functional antheridium by 
Dangeard (24a) and Brown (16). Harper and Claussen agree that 
the contents of tlie antheridium enter the oogone but disagree as to whether 
nulcear fusion occurs in the oogone. Claussen has succeeded in watching 
the stages of fertilization in living material. Tliere is of course always 
the possibility that parthenogenetic varieties of sexual species may exist, 
but with so much positive evidence of a functional antheridium in the 
mildews and Pyronema it will take a very detailed account accompanied 
by excellent figures to eonvinee botanists that some of these species are 
parthenogenetic. 
Other ascomycetes in which either one or both sexual organs are 
not produced or are not functional are Humana granulata (Blackman 
and Fraser, 11), Humana rutilans (Fraser, 36), Lachnea stercorea (Fra- 
ser, 35), Aspergillus herbariorum? (Fraser and Chambers, 37), Otidea 
aurantia and Peziza vesiculosa (Fraser and Welsford, 38), Ascobolus 
furfuraceus (Welsford, 87), Ascophanus carneus (Cutting, 22), Poronia 
punctata, (Dawson, 26), Gnomonia erythrostoma (Brooks, 15), Laboul- 
benia clxaetophora and L. gyrinidarum (Faull, 29), Lachnea scutellata 
(Brown, 17), and among the lichens Peltigera canina, P. rufescens and 
P. malacea, Peltidea aphthosa and P. venosa, Nephroma tomentosum and 
N. laevigatum (Fünfstück, 40) and Solorina saccata (Baur, 5). 
In Peltigera, Peltidea and Solorina, spermogonia are seldom or never 
found, and in Nephroma tliey are never fully developed. In Peltigera 
and Peltidea, the ascogones, as Fünfstück described and figures them, 
arise frorn undifferentiated vegetative hyphae which are gradually trans- 
formed into rows of larger swollen cells which may again terminate in 
more slender vegetative hyphae. Baur (5) confirms Fünfstück’s observa- 
tions on Peltigera canina. In Nephroma, the ascogone cells form neck- 
lace-like irregularly wound filaments. The ascogones of these lichens liave 
no triehogynes. The complex of hyphae in the regions of their young 
fruit bodies, forms a dense tissue, in which it would be difficult to follow 
any one hypha with certainty from seetion to section. In this respect such 
gelatinous lichens as Collema pulposuni are much more favorable material 
for study. Wainio (85) points out that in such forms as Peltigera, wliose 
ascogones are entirely enclosed witliin the thallus, all possibility of fertili- 
zation by the spermatia is exeluded. However, from the eonditions in 
Collema pulposum, it seems not impossible that a similar carpogone may 
exist in the genera investigated by Fünfstück. The number of tricho- 
gyne cells in C. pulposuni is less than in many other lichens, and it is 
