CRYPTONEMIALES 



229 



rounded fusion cell is formed by the auxiliary cells, and this 

 contains both fertilized and unfertilized carpogonial nuclei. The 

 antheridia are much elongated, and after liberation the spermatia 

 round off and remain attached to the antheridial wall by means of a 

 long thin pedicel in C. officinalis and by a short stalk in C. ruhens. 



CERAMIALES 

 Delesseriaceae : Delesseria (after Baron Delessert). Fig. 152. 

 The large, thin, leafy fronds, which are bright red in colour, 





Fig. 152. Delesseria sanguinea. A, plant. B, apex of thallus to show cell 

 arrangement ( x 258). C, first stage in formation of carpogonial branch, st-i = first 

 group of sterile cells ( x 408). D, later stage of same, c/) = carpogonial branch, 

 5C = support cell, 5^1 = first, and 5?2 = second group of sterile cells ( x 408). E, 

 mature carpogonial branch, sc = support cell, sti = first sterile branch, st2 = second 

 sterile branch ( x 720). F, formation of antheridia in related genus, Nitophyllum. 

 G, transverse section of mature cystocarp in the related genus Nitophyllum. 

 H, tetraspores ( x 360). (A, F, G, after Tilden; B-D, after Kylin; E, H, after 

 Svedelius.) 



