





1 



i 









Fig. 232. Cross-sections stained in haematoxylin and Bismark brown to show a comparison between 

 a prothallus and a rhizome in Psilotum nudum (L.) Beauv. (P. triquetrum Swartz). x 40. a. A diploid 

 prothallus from Rangitoto Island showing central area free from the endophytic fungus though 

 this specimen is without actual tracheids. Note projecting antheridia. b. Transverse section 

 of a tetraploid rhizome from Malay showing fungus and central vascular tissue. 



'I'V' 









y-~ 





Fig. 233. Vascular prothallus from Rangitoto Island to show detail of central conducting strand. 

 a. Longitudinal section. b. Transverse section. Both x 100. 



