232 On Azolla and Salvinia. 



which is now therefore more or less pedicellate. The 

 cellularity of the head or terminal part is more evident, it is 

 evidently hollow, and the cavity contains grumous matter 

 (PL 17. f. 6. 7.) As it goes on enlarging the head assumes 

 a spherical form, the pedicel becomes more developed, the 

 grumous mass larger (PL 17. f. 8. 9. 10.) 



Then in the cells of the heads, which are the young 

 secondary capsules, amylaceous granules (for they are 

 violetted by indigo) appear. And at this period, if the 

 grumous mass be closely examined, very minute cells will 

 be seen in it, each cell containing 3 or 4 nuclei (PL 17./. 11. 

 12.) (or perhaps three or four cells each containing a nucleus) 

 convex exteriorly, trifacial interiorly.'* 



The enlargement continuing, the next stage presents the 

 formerly grumous mass as cellular, the membrane of the 

 cells (the parent cells) not well developed, with grume along 

 their contiguous faces. (PL 17./. 13.) In each of these 

 cells are 3 or 4 yellow nuclei presenting more or less of 

 their original connection, or quite distinct. Examined 

 separately each of these presents a convex surface and 

 a trifacial one, the last being the surface of their former 

 contiguity. The parent cells soon cease to be evident, 

 and then the cavity of the s. capsule appears filled more 

 or less with trifacial yellow cells (PL 17. f. 14.) 



At a later period each head (or s. capsule) presents the 

 appearance of being subdivided into several cellular-looking 

 compartments, each of which encloses several of the yellow 

 sacs (PL 17. f. 15.) The yellow sacs, when separated, 

 present no particular change, appearing generally quite 

 empty (PL 17. /. 16.) 



Still later each s. capsule presents generally three or some- 

 times two subdivisions of increased size (PL 17. f. 17. 18.) 

 And this is nearly the mature form, for the further changes 



* Trifacial if three are developed as is most usual, quadrifacial, if four. 



