On Azolla and Salvinia. 271 



4. An organ (ovulum) in its perfect state, with a much 

 younger one (No. 2) at its base. The supposed fe- 

 cundating matter shewn in application to the foramen. 

 5. 6. An organ much less advanced : 5 is a longitudinal 

 section. 



7. Another in its perfect state: the jointed obtuse fila- 



ments are what I take to be the male organs. The 

 supposed fecundating matter shewn in contact with 

 the foramen. It was also noted to have appeared to fill 

 the space in the organ between the nucleus and the 

 foramen. 



8. Young capsule under pressure to shew the nucleus, 



now a mass of young secondary capsules. 



9. Nucleus (or mass of young secondary capsules) of the 



same. 

 10. 11. 12. 13. 14. Represent the first developments of these 



secondary capsules. 

 15. 16. 17. 18. Continuation of the developments, ending in 



the presence of a larger cavity filled with grume in 



the secondary capsule. 



19. Long section of a capsule more advanced. 



20. One of its secondary capsules at that stage, when the 



cavity is occupied by uniform grume. 



21. Another intended to exhibit the next step, i. e. the ap- 



pearance of points of condensation (or nuclei.) 



22. Another more advanced : the parts of the circumference 



of the grume between the radiating lines have a ten- 

 dency, (shewn by iodine,) to the production of mem- 

 brane (parent-cells?) 



23. Represents a young secondary, with its cavity only 



partly filled with grume, in which two condensed 

 points (nuclei) are visible. 



24. Another about the same period, a considerable num- 



ber of membranous sacs (parent cells ?) visible in the 

 grume. 



25. Another about the same period. 



26. Ditto more advanced, the membranes, (parent cells ?) 



more developed. 



27. Another still more advanced ; at this stage the cavity 



is filled partly or entirely with grume, in which are 

 imbedded a number of distinct trifacial cells, the 

 young spores. 



