MORPHOLOGY AND LIFE HISTORY OF SOME ASCOMYCETES 
WITH SPECIAL REFERENCE TO THE PRESENCE 
AND FUNCTION OF SPERMATIA^ 
B. B. HiGGINS 
The presence of "spermatia," of "microspores," or of a ''Phoma" or 
"Phyllosticta" stage has been mentioned in connection with numerous 
species in various famihes of the Ascomycetes; but usually the function or 
the genetic connection has not been studied, consequently our knowledge 
of these structures is still very hazy. Do they occur regularly at a definite 
stage in the development of the fungus, or only under exceptional conditions? 
Do they function, like ordinary spores, as reproductive bodies for propa- 
gating the fungus; or are they sexual elements? If the latter, are they 
now functional or merely degenerate remnants? 
These are questions which have been determined for only a few species 
outside the Laboulbeniales and the lichens. The spermatia of Gnomonia 
erythrostoma were described by Frank (4) and those of Polystigma ruhrum 
by Fisch (3) ; and in both cases they were thought to be male sexual 
elements. This view has been sustained by the later studies of Brooks (2), 
and Blackman and Welsford (i), who considered them to be male sexual 
elements now functionless through degeneration of the carpogonia. Nien- 
burg (8) considered P. riihrum to be a true oogoniate with the spermatia as 
degenerate functionless elements. Miiller (7) found that the spermatia of 
Rhytisma acerinum failed to produce infection on the host plant or to 
germinate in culture media; and, failing to find carpogonia, he concluded 
that the spermatia were functionless male elements. The writer has re- 
ported the occurrence of spermatia and carpogonia in connection with the 
young ascocarps of three species of Coccomyces (5) and of Mycosphaerella 
nigerristigma (6). In these forms also the spermatia failed to germinate in 
any culture medium tried. 
Further observations have shown that similar structures occur quite 
commonly in many families of Ascomycetes; and the question as to their 
possible function has led to a study of the complete life history of several 
species, some of which have not been previously described. The observa- 
tions have been confined very largely to the species growing parasitically 
on the leaves and succulent parts of flowering plants, because of the com- 
parative ease with which such forms may be studied and of the improbability 
of the association of other species, and also because of the value to plant 
pathologists of knowing the complete life history of such parasites. 
^ Paper number 14, Journal Series, Georgia Agricultural Experiment Station. 
435 
