of Poronia punctata (L.). 257 
it is conceivable that in their growth they follow a path 
already prepared for them, by the trichogyne-like hypha. 
The Asa in their youngest stages are small club-shaped 
bodies with very abundant finely granular protoplasm, 
especially dense in the apical region, near which lies the large 
nucleus. The ascus gradually elongates ; the nucleus divides 
into two, four, and then eight, and around these the protoplasm 
aggregates. As described by Harper 1 in various Ascomy- 
cetes, the ascospores arise by free cell-formation, some proto¬ 
plasm being left over as an ‘ epiplasmic ’ layer, lining the wall 
of the ascus. This author regards such a mode of development 
as strong evidence against any close relationship between asci 
and sporangia (in which spore formation is by cleavage of 
the protoplasm, proceeding inwards from the sporangium 
walls), such as Brefeld’s theory requires. 
In spite of numerous trials, I have failed to get perfectly 
satisfactory karyokinetic figures in the division of the nucleus 
in the ascus, owing to difficulties in fixing and staining, but 
sufficiently convincing examples have been seen to show that 
two and then four nuclei are present, and that later each spore 
contains one nucleus. In the stage with the eight naked 
masses of protoplasm the free nuclei were not however clearly 
seen. The eight spores finally come to lie in a single row, 
each surrounded by a double wall, the outer of which, on 
ripening, becomes dark brown in colour, with a clearly marked 
lateral slit-like pit 2 (Figs. 28-30). When first liberated from 
the ascus, the elliptical spores are surrounded by a distinct 
gelatinous covering, resembling a halo. At the apex of the 
ascus the wall is seen to be folded in, causing the ‘ epiplasm 5 to 
form three peg-like projections, like those represented by Zopf in 
Hypocopra 3 . These are particularly obvious in the younger asci. 
The Conidia , as already indicated, arise by abstriction from 
the ends and sides of the terminal hyphae of the stromata. 
1 Harper, Cell-division in Sporangia and Asci. Ann. of Bot., Dec., 1899. 
2 This lateral marking has been omitted by Brefeld in his figure of these asco¬ 
spores, suggesting that his drawing may have been made from the other side of 
the ascus. pleft x, Taf. ix, Fig. 8. 
3 Zopf, Die Pilze, p. 92, Fig. 60. 
