204 Barker . — The Morphology and Development of 
formation of septa, the antheridial branch being usually the 
former apex of the parent hypha. Fusion then takes place 
between the two organs, followed probably by migration of 
nuclei from the antheridium into the ascogonium and sub- 
sequent fusion of these with the nuclei of the latter. The 
fertilized ascogonium then divides into a terminal cell and 
a central cell by the formation of a transverse septum, and 
possibly in some instances a third cell, the pedicel, is also cut 
off. The central cell begins to swell considerably, and becomes 
invested by hyphae, arising immediately beneath it, either 
from the parent branch or from the pedicel, when the latter 
is present. After swelling, the invested central cell produces 
one or more hyphae which develop vigorously and produce 
a mass of entangled ascogenous hyphae, which displace it 
to a certain extent, causing it to completely envelop them 
and to become closely adpressed to the enclosing investing 
hyphae. The latter soon become much flattened out and 
lose their contents, being represented in the later stages by 
a mere reticulum of brown cell-walls around the enlarged 
central cell. Asci are eventually produced from the asco- 
genous hyphae, and in each of them eight ascospores are 
usually formed. When the spores are ripe, the asci and asco- 
genous branches degenerate, the surrounding central cell 
having by this time lost its contents, remaining as a brown 
cuticularized enclosing wall. The spores are thus liberated 
into the cavity enclosed by this wall, and the ripe perithecium 
appears to be nothing more than a brown cuticularized 
sporangium-like structure. From it the spores escape by the 
degeneration of its walls. The number of spores is very 
variable. They are spherical or ovoid in shape, and possess 
thick walls. They are more or less red, brown, or orange in 
colour, and possess a very characteristic refringent appearance. 
From this description it follows that the genus must be 
placed among the Ascomycetes. At the same time it does 
not very clearly fall into any well-defined group on account 
of the curious behaviour of the central cell and the incomplete 
character of its investment. At various stages of its develop- 
