CARPOSPORE^. 
slender branches now shoot out at opposite points, and grow upwards on the outside 
of the helix ; one of these developes more quickly, reaches the uppermost coil, and 
becomes closely attached to it by its apex {B, p). This branch is the pollinodium. 
Conjugation takes place between its apex and that of the carpogonium, the cell-walls 
being absorbed at the point of contact, and the protoplasmic contents of the two cells 
commingle. Soon afterwards new filaments sprout out from the lower part of the 
pollinodium and of the carpogonium, which increase in number, cling closely to the spiral 
(C), and finally entirely envelope it. From these filaments a layer of polygonal cells (D) 
is formed by numerous transverse divisions, which envelopes the carpogonium. The 
cells of the enveloping layer grow inwards as papillae which become septate (E). While 
the enveloping layer is increasing in size, the cavity of the perithecium, which is thus 
enlarged, is filled up by the papillae, and they finally insert themselves between the coils 
Fig. 208.— Development of L'uroitum repens (after De Bary). A small portion of a mycelium, with the conidia-bearing 
hyphne c and young ascogonium (or carpogonium) as: B the spiral ascogonium as with the pollinodium /; C the same, 
beginning to be surrounded by the threads out of which the wall of the perithecium is formed ; D a perithecium ; E, F 
section of young perithecia, w parietal cells,/" pseudo-parenchyma, as ascogonium; G an ascus ; H an ascospore. 
of the carpogonium which have now become looser. These papillae become divided 
by septa into numerous cells of similar diameter, so that at last the space between 
the enveloping layer and the coils of the carpogonium is filled by a pseudo-parenchyma 
{F). During these processes a large number of septa arise in the carpogonium, and 
soon there shoot from its ceils numerous commencements of branches, which penetrate 
on all sides between the cells of the pseudo-parenchyma, become septate, and ramify. 
Their last ramifications are the asci (G), which therefore owe their origin to the 
fertilised carpogonium. These internal changes are accompanied by a considerable 
increase in size of the whole perithecium. During the development of the asci 
the pseudo-parenchyma becomes looser, its cells round themselves off, become capable 
of swelling, lose their fatty contents, and finally disappear ; in the ripe perithecium 
