confluens and the Morphology of the Ascocarp . 399 
EXPLANATION OF FIGURES IN PLATES XIX-XXI. 
Illustrating Professor Harper’s paper on Pyronema confluens . 
PLATE XIX. 
All figures were drawn with the aid of the camera lucida , and with the Zeiss 
apochromatic objectives. Figs. 3-10, 12-15, 17#, 17 19-22, and 24 with obj. 
2 mm. compens. oc. 4. Fig. 11 with obj. 2 mm. oc. 6. Figs. 2, 16, 16 a, 16 b, 31, 
42, and 43 with obj. 2 mm. oc. 8. Figs. 25-30, 32-41 with obj. 2 mm. oc. 12. 
Fig. 18 with obj. 8 mm. oc. 12. Fig. 23 with obj. 8 mm. oc. 4. 
Fig. 1. Rosette of three pairs of sexual cells drawn from surface view, the group 
slightly flattened by pressure. 
Fig. 2. Branched mycelial cell showing nuclei and granules on the septa. 
Fig. 3. Young pair of sexual organs with vegetative cells below. Trichogyne 
appears as a mere papilla on the oogonium. 
Fig. 4. Older pair, trichogyne not yet cut off from oogonium. Antheridium cut 
transversely. 
Fig. 5. Longitudinal section of antheridium. Trichogyne cut obliquely showing 
smaller nuclei. 
Fig. 6. Oogonium and trichogyne cut longitudinally. Oogonium stalk with 
budding vegetative hyphae. Trichogyne with hyaline beak, its nuclei swollen and 
transparent. 
Fig. 7. Longitudinal section of antheridium ; oblique section of trichogyne 
showing the fusion-pore. Nuclei of antheridium not yet disintegrated as they 
commonly are at this stage. 
Fig 8 b. Oblique tangential section of antheridium. Trichogyne cut transversely 
near its base and apex. Pore forming by solution of walls between trichogyne 
and antheridium. a. Remainder of same trichogyne from next section showing 
disintegrated nuclei. 
Fig. 9. Oblique section of antheridium and trichogyne showing receptive spots 
of each and formation of pore. 
Fig. 10. Pore complete and fragments of dissolved wall lying near in the 
trichogyne. Hypothecial hyphae springing from stalk-cells. Nuclei in trichogyne 
disintegrated. 
Figs. 11 and 12. Slightly later stage, receptive spots becoming spongy and 
vacuolar. 
Fig. 13. Nuclei beginning to migrate from antheridium to trichogyne. Stalk 
cut obliquely not showing hypothecial hyphae. 
Fig. 14 (Plate XX). Trichogyne filled with nuclei from the antheridium. Nuclei 
collecting in oogonium. Antheridium curved around the trichogyne so that the 
latter appears in section to cut through it. 
Fig. 15. Basal wall of trichogyne dissolved and male and female nuclei collected 
in a dense mass in centre of oogonium and fusing in pairs. Nuclei still present in 
trichogyne and upper end of antheridium. Ascogenous hyphae appearing as buds 
on oogonium. 
Fig. 15 a. Another oogonium at about the same stage as the last. 
