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Freda M. Bachmann 
ascogone cells from which the ascogenous hyphae branch off. In Pyro- 
nerna (Harper, 51), the ascogenous hyphae are septate, each cell con- 
containing several nuclei. Tlie nuclei are always two or three times the 
size of the nuclei in the vegetative hyphae and thus afford a means of 
easily distinguisliing these hyphae. There are frequently smaller nuclei 
mingled with the larger ones. These, Harper thinks, are very likely 
female nuclei which have not been fertilized. They are never found very 
far from the ascogonium. In old fruits, he finds small nuclei flattened 
against the wall of the ascogonium and becoming disorganized with the 
remaining cytoplasm. Fraser describes the nuclei in the ascogenous 
hyphae of Humana rutilans as larger than those in the surrounding cells. 
Claussex (20) finds no fusion of male and female nuclei in the oogonium 
of Pyronema, but only a pairing. The female nuclei are considerably 
larger than the male nuclei at this time, but this difference in size later 
disappears. In the ascogenous hyphae the nuclei are paired but about 
the same size. The cells contain a dense plasma content. In Ascobolus 
(Harper, 49), the ascogenous hyphae are septate; those cells next to 
the ascogone are without content and later become disorganized like the 
cells of the ascogone. The nuclei of the ascogenous hyphae, as in Pyro- 
nema, are at least three times as large as those of the vegetative hyphae. 
The ascogenous hyphae arise only from one of the central cells of the 
ascogonium. In Ascoplianus carneus (Cuttixg, 22), the greater part of 
the cytoplasm is aggregated in the more distal cells of the ascogenous 
hyphae. The cells nearest the ascogonium become more and more vacuo- 
lated and the nuclei seem to degenerate. The number of nuclei in a cell 
varies from one to three or five. These hyphae come from several cells 
of the ascogonium. 
In Pliyllactinia (Harper, 52), the cells of the ascogenous hyphae 
are uninucleate with the exception of those which are to become asci. 
These contain two nuclei each. Harper was not able to determine whether 
the ascogenous hyphae arise from more than one cell of the ascogonium, 
but at least some of them come from the penultimate cell which regularly 
contains more than one nucleus. Barker (6, 7) found that the ascogo- 
nium in Phyparobius becomes several celled. These cells are at first 
uninucleate, later binucleate or even quadrinucleate, and give rise to 
the ascogenous hyphae. Some of the cells of the ascogenous hyphae 
contain two nuclei which probably fuse to form the primary ascus nucleus. 
Overton (72) observed that the ascogenous hyphae may arise from any 
or all of the cells of the ascogone in Thecotheus and develop considerably 
before they become septate. When the cell division is complete the 
