tort] BROW N—LACHNEA SCUTELLATA 299 
ascus is formed by the fusion of a nucleus from the oogonium 
and one from the antheridium. 
Among the Erysibaceae, HARPER (19, 20, 23) has described the 
fusion of a uninucleate antheridium and oogonium in Sphaero- 
theca humuli, Erysiphe communis, and Phyllactinia corylea. Accord- 
ing to Harper, the male and female nuclei fuse in the oogonium, 
and this is followed later by a second nuclear fusion in the ascus. 
DANGEARD (9, 10) has studied the development of Sphaerotheca 
humuli and Erysiphe, and denies the presence of a fusion in the 
oogonium. 
BARKER (2) has described the fusion of an antheridium and 
oogonium in Monascus. He did not find a fusion of nuclei in the 
oogonium, but attributed this to his failure to get the proper 
Stages. SCHIKORRA (33) has also described the fusion of an 
antheridium and oogonium in Monascus, but does not find any 
fusion of nuclei except the one in the ascus. 
Among the Pezizineae the fusion of nuclei in pairs in the ascogo- 
nium has been described in Pyronema confluens (HARPER 22), 
Humaria granulata (BLACKMAN and FRASER 3), Lachnea stercorea 
(FRASER 13), Ascobolus furfuraceus (WELLSFORD 36), Ascophanus 
carneus (CUTTING 7), and in the vegetative hyphae in Humaria 
rutilans (FRASER 14). In all of the above cases a second fusion is 
described in the ascus. CLAUSSEN (8), however, after studying 
Pyronema confluens, has concluded that there was no fusion of 
nuclei in the ascogonium. BRown (4) came to the same conclusion 
in regard to a form of this species in which the antheridium did 
not fuse with the trichogyne. This conclusion was confirmed by 
the behavior of the chromosomes in the ascus. In Lachnea it 
would seem to be quite evident that there is no fusion of nuclei in 
the ascogonium, but there are appearances connected with division 
Which may be readily mistaken for fusions. During prophase, 
when the nuclei are of course large, the massing of the chromosomes 
into a nucleolus-like group gives an appearance much like a fusion 
nucleus, while the reorganization of fusing nuclei in contact simu- 
lates fusing nuclei rather closely. Similar appearances have been 
seen by the writer (BRowNn 4) in Pyronema. In view of these 
facts and the increasing amount of negative evidence, it would 
