420 



BOTANY 



PART II 



head cells project. The latter form 3-6 secondary head cells, and from 

 each of these arise 3-5 long unbranched spermatogenous filaments. 

 These are composed of disc-shaped cells from each of which a spirally- 

 wound spermatozoid with two cilia is liberated 

 (Fig. 362 C). The spermatogenous filaments 

 or antheridia may be compared morphologi- 

 cally to the plurilocular gametangia of the 

 Brown Algae. These, as in Stilophora for in- 

 stance, may consist of simple rows of cells and 



c/ 



FIG. 362. Chara fragilis. A, Median longitudinal section through a lateral axis r, and the sexual 

 organs which it bears (x 60); a, antheridium borne on the basal nodal cell na, by the stalk 

 cell p ; m, manubrium ; db, an oogonium ; no, nodal cell ; po, the stalk cell ; v, pivotal cell 

 (Wendungszdle); c, the crown. B, A lateral axis ( x 6) ; a, antheridium; o, oogonium. C, 

 Spermatozoid ; k, nucleus ; cl, cilia; c, cytoplasm (x 540). (After STRASBURGER.) 



be grouped together in sori. The male organ of the Characeae, which 

 as a whole is commonly spoken of as an antheridium, thus contains 

 eight groups of endogenously-formed antheridia and should on this 

 account be termed an antheridiophore. 



The female organ (Fig. 362 ob) consists of an oogonium which 

 contains a single egg-cell with numerous oil-drops and starch grains. 

 To begin with, the oogonium projects freely, but later becomes sur- 

 rounded by five spirally-wound cells. These cells end in the corona, 



