Igt1] BROW N—LACHNEA SCUTELLATA 283 
described, the nuclei undergo division in the ascogenous hyphae, 
so that the two nuclei which are in the tip of a hypha are probably 
closely related. There appears, moreover, as has been previously 
pointed out (BRowN 6), to be no reason for thinking that the rela- 
tion of fusing nuclei can make any difference, if these are all in the 
same plant and are derived from a single nucleus, with the haploid 
number of chromosomes. 
The nuclei in those cells of the ascogenous hyphae which are 
below the hymenium finally degenerate. In doing so they often 
swell up to several times their original size, after which the nuclear 
membrane gradually disappears. This process is quite similar 
to that described by HARPER (22) for the nuclei in the trichogyne 
of Pyronema confluens. Before degenerating two or three of the 
nuclei sometimes fuse togethér. Such fusions are not confined to 
the nuclei of the ascogenous hyphae, but may occur in other 
degenerating cells. 
The binucleate cells previously described as being formed from 
the ascogenous hyphae grow up in the hymenium and bend over 
at the tip. The two nuclei pass into the bent portion and divide 
in the same manner that has been described for the nuclei in the 
ascogonium (fig. 17). At metaphase there are five chromosomes, 
and at anaphase five pass to each pole. Walls come in between 
the daughter nuclei of each pair, thus forming a binucleate penulti- 
mate and a uninucleate ultimate and antipenultimate cell (fig. 18). 
This is of course a typical hook. The two nuclei in the penulti- 
mate cell may fuse to form the nucleus of an ascus (fig. 20), but 
often they divide and give rise to the nuclei of another hook (fig. 24). 
The ultimate cell usually grows down and fuses with the stalk 
(fig. 19), after which the nucleus from the stalk usually migrates 
into the ultimate cell (fig. 21), although occasionally the nucleus 
of the ultimate cell may pass into the stalk. After the nucleus 
of the stalk has migrated into the ultimate cell, it may fuse with 
the nucleus of the ultimate cell to form the primary nucleus of an 
— ascus (fig. 22), but usually the two nuclei divide and the ultimate 
cell grows out to form another hook (figs. 23, 24). Sometimes the 
nucleus formed by the fusion of the nuclei of the ultimate and ante- 
Penultimate cells does not develop further. This is usually asso- 
