SE en ais ge rag ee el Seer ee eS oe Ay) oe ae See 
1910] BROW N—ASCOCARP OF LEOTIA 453 
Thelebolus stercoreus (RAMLOW 24), Humaria granulata (BLACK- 
MAN and FRASER 4), Lachnea stercorea (FRASER 13), and Asco- 
phanus carneus (CUTTING 7). 
As has already been pointed out, the origin of the hymenium, 
including the storage cells and the formation of the asci, is also 
similar to the same process in some of the Pezizineae. 
The presence of an elongated stipe, moreover, is of frequent 
occurrence among the Pezizineae, while a tendency of the hymenium 
to become recurved is shown by many of them. A comparison 
of figs. 45 and 46 will show the similarity in form between Leotia 
and an old specimen of Pyronema confluens. 
From the above considerations it would seem that Leotia is 
as closely related to some of the Pezizineae as some of them are 
to each other, and it is probable that the ancestors of Leotia were 
closely similar to some of them. 
Relationship of the fusing nuclei 
According to what is probably the most prevalent interpreta- 
tion, the fusion in the ascus is regarded as being of a vegetative 
character, and so the relationship of the fusing nuclei is considered 
to be of no great significance. This interpretation is based on the 
presence of a supposed fusion of nuclei in the ascogonium. Such 
fusions have been described in Pyronema confluens (HARPER 16), 
Humaria granulata (BLACKMAN and FRASER 4), Lachnea stercorea 
(FRASER 13), Ascobolus furfuraceus (WELSFORD 28), Humaria 
rutilans (FRASER 12), and Ascophanus carneus (CUTTING 7). 
CLAUSSEN (8), however, after a study of Pyronema confluens, has 
come to the conclusion that the fusion in the ascus is the only one 
that occurs in that species. BRown (5) has described a form of 
Pyronema confluens in which the antheridium does not fuse with 
the ascogonium, and in this case he fails to find a fusion of nuclei 
in the ascogonium. The cytology of the ascus confirms this inter- 
pretation. There are, however, appearances in this form very 
much like fusing nuclei, which are due, however, to the fact that 
the daughter nuclei reorganize close together. BARKER, in studying 
Monascus, failed to find a fusion of nuclei in the ascogonium, but 
attributed this to his failure to get the proper stages. SCHIKORRA 
