198 DIVISION II.—COURSE OF DEVELOPMENT OF FUNGI. 
transverse diameter of the mycelial hypha 10 times or more (4). Then they cease to 
lengthen, are delimited from their parent-hyphae and conjugate at their summits, the 
cell-walls disappearing at the point of contact and the two protoplasmic bodies 
coalescing into one (c). The place of conjugation then swells into a spherical vesicle, 
which is delimited when the protoplasm of the pair of cells has passed into it, and 
having thus become an ascus forms 8 spores capable of germination (d-f). The 
spores are formed, as far as can be gathered from. Eidam’s somewhat superficial 
description, in the manner described in section XIX. No further complications have 
been observed in the formation of these sporocarps. 
2. Distinct archicarps are formed as branches on the mycelium or on vegetating 
hyphae in the thallus singly, or rarely in groups, as in Pyronema and Physma. It 
depends on the species whether the archicarp is a single cell or, as is more com- 
monly the case, a cell-row, and whether it is spirally coiled or of some other shape. 
The whole ascus-apparatus of the sporocarp is derived exclusively from the archi- 
carp. In Podosphaera a single ascus borne on a short stalk-cell is formed by 
transverse division of the uni- 
cellular archicarp; in other species 
ascogenous hyphae sprout as 
a branches from the .archicarp, or 
the cells of the archicarp divide 
into ascogenous daughter-cells, 
that: is, into daughter-cells which 
b sprout out into asci. The archi- 
carp takes no part in the forma- 
tion of the envelope-apparatus, 
that is, of the wall, receptaculum, 
excipulum, paraphyses, &c. This 
Sie cet he ea ees eee has TS onen. mn the hyphal 
matured and the spores formed in it. After Eidam. Magn. goo times. branches which arise in the neigh- 
bourhood of the archicarp, usually 
at its base, and grow round the ascus-apparatus in a way which is determined by 
the species. From this specific ascogenous function the archicarp may in this case 
be termed an ascogonium. It has also been called a carpogonium. Of cleistocärpous 
and pyrenocarpous forms the Erysipheae, Eurotium, Penicillium, Sordaria 
(Hypocopra), and Melanospora parasitica belong to this section; of gymno- 
carpous and discocarpous forms Gymonoascus, Pyronema, Ascobolus, and the 
Collemaceae which were examined by Stahl (Collema, Synechoblastus, Leptogium, 
Physma, &c.). 
In a number of the species of this division an antheridial branch makes its 
appearance in characteristic form in connection with the archicarp before the com- 
mencement of the formation of asci. This is the case especially with Pyronema, 
the Erysipheae, Hypocopra, Gymnoascus, and Eurotium. In Pyronema, before further 
development begins, conjugation, the union of the two protoplasmic bodies into one, 
takes place between antheridial branch and archicarp, by means of a special appa- 
ratus, belonging to the archicarp, the /richogyne, and the same thing happens in 
less striking form in Eurotium. In the Collemaceae the antheridial branches are 

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