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spore, remains indefinite in both series. According to this view, all of 
the higher fungi had their origin in Zygomycetes, and the two series 
simply developed in different directions, one series excluding sporangia 
and developing specialized conidiophores (basidia), while the other 
series retained indefinite conidiophores, but developed sporangia of 
a very precise character (asci). 
The Hemiasci consist of three families, (1) Ascoidera, (2) Protomycetes, 
and (3) Theleboleje. In these simple forms the sporangium becomes 
ascus-like, but is still indeterminate as to form, size, and number of its 
spores. The spores are usually shot out with considerable force, show¬ 
ing in this particular a greater adaptation to terrestrial life than is 
found in most Zygomycetes. The Ascokhe have free sporangia, as in 
Mucor, and conidia. The Protomycetes also have free sporangia and 
conidia, but the former are preceded by chlamydospores. The Thele- 
bolem have sporaugial fruits, the condition seen in Mortierella rostajin - 
slcii having been carried a step farther by the reduction of the sporau 
giophore to a mere rudiment and the extension of the basal weft of 
mycelium into an envelope. 
The Ascomycetes are characterized by the preseuce of the aseus, 
which is simply a sporangium that has become determinate in form, 
size, and number of its spores. In very many cases this form of fructi¬ 
fication is accompanied by conidia and chlamydospores. When ripe 
the spores of most Ascomycetes are shot out of the aseus with great 
energy. Sexual organs do not occur in any of the forms, and the earlier 
observations ascribing sexuality to various Ascomycetous fungi are 
misinterpretations. The Ascomycetes are divided into Exosporangial 
and Carposporangial forms. The Exoasci are the simpler, having naked 
asci, borne directly on the mycelium. They include two families, Endo- 
mycetacem and Taphrinere. The Oarpoasci, which form the bulk of the 
Ascomycetes, have fruit bodies. The asci are not naked and do not arise 
directly from the mycelium, but in special organs, which are composed 
of fertile or asci-bearing hyplne, and of sterile threads, which form the 
walls of the envelope. In most cases asci are not borne singly, but in 
great numbers in a hymenial layer. The simplest aseus fruits are angio- 
carpous. In the more highly differentiated Pyrenomycetes they have a 
special ostiolum. In another series of forms, i. e., Hysteriacem and Dis- 
comycetes, the fruit body may be called gymnocarpous, being closed at 
first but afterward open. Of much importance in the Oarpoasci are the 
accessory fruit forms. In addition to ordinary free conidia and chlamy¬ 
dospores, there are conidia which have reached a higher grade of devel¬ 
opment, being produced within special fruit bodies resembling aseus 
fruits (the pycnidia). Still another fruit form is possible in this group, 
but has not been found, viz, ordinary sporangia. The simplest form 
of conidia appears in the Taphrinese, being developed directly from the 
ascospore, even before its escape from the aseus, or else from another 
conidium. The next advance is the production of a germ tube on which. 
23192—No. 4-5 
