Fig. 87 Spermatochnus paradoxus. A, plant ( x 0-44). B, apex of 

 young plant showing origin of cortication. C, portion of old thallus 

 showing structure, a = assimilator , c= cortical cells, c/ = central 

 filament, h =hair, m = mucilage. D, portion of thallus showing cor- 

 tication and pairs. E, paraphyses and tmilocular sporangia ( x 200). 

 (A, E, after Newton; B-D, after Oltmanns.) 



life q^cle has not yet been worked out, but if it is at all comparable 

 with the other closely related genera then the zooids should give 

 rise to a microscopic gametophyte generation. 



NOTHEIACEAE : Notheia (a spurious thing). Fig. 88 



The filiform sporophyte grows out parasitically from the base of 

 conceptacles of the Fucalean Hormosira hanksii (see p. 212) and 

 on itself. There is an apical growing zone of three cells which give 

 rise to filamentous rows of cells. Later divisions in different planes 

 lead to a parenchymatous thallus in which epidermis, cortex and 

 medullary tissue can be distinguished. The apical filamentous 

 development is characteristically ChordaHan and in its anatomy 

 the plant has features reminiscent of both Spermatochnus (see 

 above) and Splachnidium. True branching is rare, such branches 

 being recognized by the lack of any basal constriction. Most of the 

 apparent branches, which are constricted at the base, represent 

 new plants that have developed from zygotes produced on a 

 filamentous gametophyte that grows inside the conceptacle. In 

 those portions of Hormosira that are attacked by the parasite the 



158 



