CrtYPTOGAMS 



IT'.t 



(Fig. 297). The ^-gg cells are produced in ooyoiiia 

 (Fig. 295), found in cavities or conceptades (Fig. 294), 

 which make their a2)pearance at cer- 

 tain seasons in sj^ecial portions of the 

 branching tliallus (Fig. 293). Tlie 

 antherozoids originate in aiitln'ridia 



293. A Biaiirh of Rock- 

 weed : ,/', a fertile 

 portion. 



— Thurbt. 



294. Section of a conceptacle. — Thttrei-. 



(Fig. 296), enlarged cells produced 

 on branching filaments. The anther- 

 idial filaments grow from the walls of conceptades, either 

 with the 0(")gonia, or in other conceptades upon separate 

 plants, according to the species of 

 Rockweed considered. At maturity 

 both egg cells and antherozoids escape 

 from the concepta- 

 d<\s and float al)()ut. 

 The antherozoids 



swai'in aljout tlie 

 naked egg cell ener- 

 getically (Fig. 297 ), 

 and one of them 

 ) finally penetrates and 

 fuses with it. At 

 a wall begins 



295. An 



once 



An anlhericlial 

 branch ; a, an- 

 tlio'iilia. 



— Thukei. 



Thuret. 



to form about the fertilized egg, or 

 oosjyore, which now settles to the bottom, and upon ger- 

 mination gives rise to a new plant. 



