294 
WILLIAM H. BROWN 
the trichogyne. After the nuclei degenerate, the antheridia become 
vacuolated and their contents degenerate. In the form described by 
Harper vacuoles appear in the antheridia after the nuclei have migrated 
into the trichogyne and at an earlier stage than in the variety in- 
igneum. The behavior of the antheridia and their nuclei, as just 
described, would seem to be sufficient to show that the nuclei do not 
migrate into the trichogyne in the variety inigneum. 
The development of the ascogenous hyphae is in accord with 
Harper's description. They grow out from the ascogonium as large 
branching hyphae, at the ends of which the asci are formed. The 
nuclei from the ascogonium migrate into these hyphae in an irregular 
manner and not in pairs as described by Claussen ('12). This early 
pairing of nuclei would not be expected in the variety inigneum for 
Claussen believes that each pair is composed of a nucleus derived 
from the ascogonium and one from the antheridium. A considerable 
proportion of the nuclei of the ascogonia never migrate into the 
ascogenous hyphae but degenerate in situ. 
No fusion of nuclei, except of degenerating ones, was observed 
in the ascogonium or ascogenous hyphae, the only one observed being 
the usual one in the asci. There were, however, appearances re- 
sembling fusing nuclei. When the nucleus is preparing for division 
and is consequently large, the spireme or chromosomes frequently 
contract into a rather dense mass resembling a second nucleolus. 
The nucleus at this stage might readily be taken for a fusion nucleus. 
Also just after division, the daughter nuclei may reorganize so close 
to each other as to be pressed together and thus look like fusing nuclei. 
These phenomena have been described by the writer in detail in 
Lachnea (Brown, '11). The figures presented in the paper on Lachnea 
answer Claussen's criticism of the note on Pyronema. 
The asci are formed from hook shaped hyphae at the tips of the 
ascogenous hyphae in the usual manner. Two nuclei divide simul- 
taneously into four which become arranged in a uninucleate ultimate 
and antipenultimate cell and a binucleate penultimate one. The 
penultimate cell may then produce an ascus or a second hook. The 
ultimate and antipenultimate cells usually fuse, the nucleus of the 
antipenultimate one passing into the ultimate, which may then form 
another hook as figured by Claussen ('12) instead of degenerating as 
described by Harper ('00). This proliferation of the hooks, with 
an increase in the number of asci formed, has been described by Mc- 
