594 
Dale . — Observations on Gymnoascaceae. 
DESCRIPTION OF FIGURES IN PLATES 
XXVII AND XXVIII. 
Illustrating Miss Dale’s paper on the Gymnoascaceae. 
Figs. 1-32. Gymnoascus Reessii. 
Fig. 1 a . Part of the original material, consisting of hard thick-walled hyphae 
and loose ascospores. (2.F.) 
Fig. 1 b. The spores more highly magnified. (4*F.) 
Fig. 2 a-d. Germinating ascospore. 
Fig. 3. Photograph of young colonies growing on a dry substratum in a culture 
plate. 
Fig. 4. Photograph of similar colonies on a wet substratum. 
Fig. 5. Photograph of older colonies in which the upper part of the mycelium 
grown on a wet substratum is becoming flocculent. 
Fig. 6. Drawing of a mycelium on a wet substratum. 
Fig. 7. An older stage of the same, in which the aerial hyphae are separating 
from one another. 
Fig. 8. Still older stage of the same. 
Fig. 9. Early stage in the formation of the sexual organs. 
Fig. 10. The sexual organs more twisted round one another. 
Figs. 11 and 12. Surface views of conjugating sexual cells. In 11 the two cells 
are of the same shape and size, in 1 2 one is larger ; but both are coiled. 
Fig. 13. A similar stage where one cell is much straighter than the other. 
Fig. 14. A later stage of a form like that in Fig. 13. a, the outgrowth of the 
* ascogone.’ 
Fig. 15. Two coiled cells after conjugation, showing the outgrowth a. 
Fig. 16. Section of a similar stage, showing nuclei. 
Fig. 17. Section of the segmented outgrowth round the end of the ‘ sterile cell.’ 
Fig. 18. The segments of the outgrowth forming branches which are the 
ascogenous hyphae. 
Fig. 19. Surface view of segmented and branching outgrowth, a , vegetative 
hyphae. 
Fig. 20. Group of ascogenous hyphae produced from a pair of sexual cells. 
Fig. 21. Section showing vegetative hyphae springing from the base of the 
sexual organs. 
Fig. 22. Section of young sexual cells, each containing a single nucleus. 
Fig. 23. Later stage, after nuclear division and the formation of a dividing wall 
below the ‘ sterile cell.’ The nuclei have increased in size, and show a distinct 
nucleolus and nuclear zone. 
Fig. 24. A later stage in which the nuclei have undergone division. 
Fig. 25. A still later stage in which the nuclei are more numerous and smaller. 
Fig. 26 a , b , c. Conjugating sexual cells in transverse section. 
Fig. 27. The same in longitudinal section, showing many small nuclei. 
