PSILOTUM. 



8. Enlargement of the secondary parent cells, which appear 

 immersed in grume or amorphous tissue. Primary parent 

 cells obsolete, disappeared ? Sporula in all marked out, 

 in some, quite distinct, and without adhering grume. 

 So far advanced as to present traces of the outer hyaline 

 membrane. 



Many nucleary discoid oblong bodies, these are the 

 young sporules which have escaped (in the section) 

 from the secondary parent cells. 



I have not seen a corresponding division of the se- 

 condary parent cell, but as it suffers a slight indentation 

 between each spore, from the analogy of Isoetes it is 

 assumable that it does not become divided prior to dis- 

 appearance. 



9. Cells filled with the young spores, which though the 

 secondary parent is not observable even in iodine or ni- 

 tric acid, remain grouped quaternary, offering all sorts 

 of appearanec from ovate to oblong reniform, etc., ac- 

 cording to their direction when seen. They have 

 now their perfect form : contain slight grume, and gene- 

 rally a nucleus. Smaller granules (not those visible 

 before, but amylaceous,) occur with the ordinary green 

 mobile granules. 



10. Cells filled with the young spores in innumerable 

 quantities, and although often quaternarily grouped, no 

 evidence of parent secondary cells occurs, the sporules 

 appear to be loosely immersed in grumous matter. 



They have the mature form, the centre occupied by 

 light grume, either semi-transparent, and ending by a 

 coniform cell, or hyaline cavity. 



11. Membranes all formed, central cavity has an incrusted 

 appearance, from producing on its surface young cells. 

 A nucellus visible. 



12. Perfect sporules, uniform oblong reniform, convex out- 

 wardly, and triagonal inwardly, of 3 membranes, the out- 

 er hyaline, distinguishable only with very high powers, 



3 p 



