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190 DopGE: RELATIONSHIPS OF FLORIDEAE AND ASCOMYCETES 
gonium. All sterile hyphae, paraphyses and secondary mycelium 
originate as the result of the branching of hyphae which grow out 
from the base of the ascogonium—from the cells below the ascog- 
enous cell, which I have called the stalk of the archicarp (Fic. 9, 
A). The ascogonium is quickly and completely enclosed by a 
thick protective layer. This peridium is not broken open at the 
apex of the young fruit by the upward thrust of the paraphyses 
but remains entirely closed until the spores are ripe and the asci 
then push their way up through the enveloping layer. The young 
hymenium is not exposed to view by the breaking open of an outer 
wall. The first appearance of the young fruit is that of a smooth 
globular structure, and later one discovers the tips of asci pushing 
up between the cells of the upper surface. Sections of entirely 
closed fruits often show several well formed asci with the eight 
spores nearly ready for dispersal (Fic. 9, A). The hypothecium is 
rather poorly developed. The asci often arise from a point below 
the ascogenous cell since the ascogenous hyphae grow downward 
as well as upward. My diagram shows to what a large extent the 
asci occupy the inner space of the fruit. Ascobolus immersus and 
A. Leveillei have much the same sort of ascocarp and originate 
from the same kind of an ascogonium. From the data just given 
it is plain that further subdivisions of the two main types of 
apothecia can be distinguished. 
According to Overton (70) the fruit body of Thecotheus is a 
compound apothecium. Baur (8, 9), Darbishire (32), and others 
have described many species of lichens in which several ascogonia 
take part or are present at least in the formation of each apothe- 
cium. Ascodesmis and Pyronema are the well-known cases where 
the rosette of sex organs arises as the result of the dichotomous 
branching of single hyphae. Ramlow (73) concludes that where | 
more than one ascus is found in Thelebolus this came about by 
accidental inclusion of two or three ascogonia in the same fruit, 
thus simulating what one frequently finds in Helotium citrinum 
and Pyronema confluens although in the latter form each of the 
fusing apothecia is in itself compound. 
If we apply these data as to the method of origin of the ascocarp 
in estimating the value of current classifications of the Ascomycetes 
we must conclude that the arrangement in a linear series of the 
