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1906] OVERTON—THECOTHEUS PELLETIERI 463 
formation obtains in general in the whole group of Ascomycetes, or 
even in nearly related genera, is clearly evident from a study of the 
more recent cytological investigations, especially those of Marre, 
GUILLIERMOND, and Fauit. In the following résumé no pretense 
of absolute completeness is made. 
We may note first those very simple forms which have sometimes 
been classed together as Hemiasci, though in most cases, as KUYPER 
shows, the types are plainly not closely related. The genera Ascoidea 
(Popra ’99), Protomyces (SAPPIN-TROUFFY ’97, PoPTA ’99), and 
Taphridium (JuEL :02) possess a septate mycelium with multi- 
nucleate cells, from which the sporangia arise directly without the 
intervention of sexual organs. The hyphal cells of Protascus (DAN- 
GEARD :03) also give rise directly to the asci. Sexual organs are 
present in Dipodascus (JUEL :02) and Eremascus (ErDAM 83), 
and the fertilized oogonium forms a single ascus. Monascus (BARKER 
:03, OLIVE :05) apparently forms a branched ascogenous hyphal 
system, each cell of which is able to produce an ascus. The hetero- 
geneity of these forms is evident by the fact that the asci arise 
directly from an oogonium, from hyphal cells, or from the cells of 
ascogenous hyphae. 
n some yeasts the conidia become transformed immediately after 
nuclear fusion into so-called asci, as in Schizosaccharomyces and 
Zygosaccharomyces, while in others the conidium is transformed 
directly into the ascus and fusion comes later, as in S. Ludwigit 
(GUILLIERMOND :05). 
In the Exoasci the binucleate cells of the mycelium are transformed 
immediately into a single ascus, as in Exoascus dejormans (DANGEARD 
94) and Taphrina (SADEBECK ’93, IKENO :OT, :03). Among the 
Gymnoascaceae, G. Reesii and G. candidus (BARANETZEY °72, Emam 
"83, DaLE :03) have their asci arising from the end cells of a series of 
short ascogenous hyphae. If CLAUSSEN’S (:05) Boudiera is really 
Ascodesmis nigricans, as CAVARA (:05) believes, and if Ascodesmis 
belongs among the Gymnoascaceae, then we have a form in this group 
whose asci arise from the penultimate cells of the recurved tips of 
the ascogenous hyphae. 
rable variation in the method of 
The Perisporiaceae show conside 
ascus formation. The early works of DEBARY and others may be 
