Macrosporium parasitiaun, Thiim. 23 
Usually, in a day or two, some branches were sent out from 
the rounded cells at the base. These branches grew and anas- 
tomosed freely with other hyphae. The cells, as in the other 
cases, were filled with fatty globules, when they ceased to grow, 
and gradually assumed a brownish colour. Fig. 24 represents 
one of these trichogyne-like processes in a culture which has 
been kept for about four months. 
It must be noted here, that in all the cultures, in which 
these abnormal hyphae appeared, an abundance of perithecia 
were also formed on the main hyphae in the manner already 
described. 
Though there are great differences in appearance and mode 
of growth between these abnormal hyphae and the hyphal 
clusters observed by Brefeld 1 on the mycelium of Peziza 
tuberosa , it is certain that they were alike produced under 
similar stimuli, — the presence of plentiful nourishment, and of 
a solid impenetrable substratum. 
Whatever the function of these abnormal bodies may be 
under such a circumstance, one cannot help recalling, on 
seeing these hyphae in a young growing stage, some of the 
sexual organs represented in other groups of Ascomycetes. 
So striking is the resemblance between them, that I venture 
to suggest that under undue stimuli the hyphal branches of 
this fungus might have produced by reversion traces of their 
long-lost character, which became useless and disappeared on 
the acquisition of the power of the purely non-sexual forma- 
tion of its perithecia. 
Recapitulation of the principal results obtained. 
1. The ascosporous stage of Macrosporium parasiticum , 
Thiim., is the common Pleospora herbarum (Pers.), Rabenh. 
2. Macrosporium parasiticum , Thiim., is identical with 
Macrosporium Sarcinula , Berk. 
3. Pleospora herbarum is decidedly a facultative parasite. 
1 O. Brefeld, Untersuch. iib. Schimmelpilze, Heft 4. p. 112. t. ix. Fig. 15 a, b. 
1881. 
