446 EXPLANATION OF THE FIGURES. 



FIG. 



3. A ripe spore beginning to germinate, three days after sowing, x 300. 



5 9. Germinating spores more developed; six days after sowing, x 100. 



Fig. 6 is fig. 5 turned round 45; fig. 7 is the same object turned round 



90; fig. 8 turned round 270. 



1 0. A germinating spore whose first capillary root is just breaking through the 



exosporium, x 300. 

 11 14. Sections of spores more advanced in germination ; figs. 11 and 14 seen 



from above, figs. 12 and 13 from the side. Figs. 11 13 are magnified 



300, fig. 14, 150 times. Figs. 13 and 14 represent spores eleven days 



after sowing. 



15. Fore-end of a somewhat more developed germ-plant, 36 days after sowing, 



seen from above, x 200. 



16. Longitudinal section of a similar fore-end, x 200. 



17. Fore-end of a germ-plant 42 days after sowing, x 200. 



18. Germ-plant 49 days after sowing, x 30. 



19 22. Half-developed spring shoots of fertile specimens, x 5. 



23. Half-developed spring shoot seen from above, x 200. 



24, 25. Longitudinal section, perpendicular to the surface, of half-developed 



shoots of fertile plants fig. 24, x 200 ; fig. 25, x 400. 



26, 27. Longitudinal section, perpendicular to the surface, of young shoots of 

 barren plauts, x 200. 



28. Transverse section of an older shoot of a barren specimen which bears four 



rudiments of adventitious shoots. Very delicate fungoid threads are 

 seen upon the outer surfaces of the epidermal cells of the mother-shoot. 

 X 200. 



29. Longitudinal section of a rudimentary antheridium, x 300. 



30. Longitudinal section of an unusually slim antheridium almost ripe. The 



contents of the cells, and the mother-cells of the spermatozoa, are not 

 shown, x 200. 



31"> J . Mother-cell of spermatozoa from an unripe antheridium, x 600. 

 32"' *. The same after its escape from a ripe antheridium. The included spiral 

 spermatozoon is already revolving, x 600. 



33 3 '*' c . Free spermatozoa, killed by iodine. In 33" and 33 c the mother-cell is 

 attached to the hinder end. x 600. 



PLATE V. 



r-ELLIA EPIPUYLLA. 



1. Vertical longitudinal section of a shoot bearing the rudiments of archego- 



nia, x 30. 



2. A similar shoot with more developed archegouia, x 30. 



3. Longitudinal section of a very young archegonium, x 400. 



4. Longitudinal section of the upper end of a somewhat more developed 



archegonium, x 300. 



