158 



LYCOPODULES 



[CH. 



wards altered to Xenophyton radiculosum^ and for which we may 

 now substitute Stigmaria radiculosa (Hick). Prof. Williamson 

 expressed the opinion that Xenophyton exhibited considerable 

 affinity with Stigmaria ficoides and Weiss's further study of the 

 species leads him to regard Hick's plant as probably the Stig- 

 marian organ of Lepidodendron fuliginosum. The diagrammatic 

 transverse section represented in fig. 177, A (4-5 cm. in diameter), 

 shows an outer cortex of parenchyma, c', consisting in part of 



Fio. 178. Rootlet of Stigmaria. (From a section in the Manchester Collection.) 



radial rows of secondary tissue and of a band of compact paren- 

 chyma bounded by the wavy line a; at sc is a series of secretory 

 strands exactly like those in a corresponding position in Lepido- 

 dendron fuliginosu77i and other species of the genus. The greater 

 part of the organ is occupied by a lacunar and hyphal middle 

 cortex identical in structure with that shown in fig. 178, B, drawn 

 from a rootlet. At d, fig. 177, A, the middle cortex has been 



1 Hick (932). 



