EXPLANATION OF PLATE XXVII. 



Blechnoxylon talbragarense, Eth. fil. 



Fig. 12. Longitudinal section of portion of a caiidex, prepared for the 

 microscope. The centre lepresents either the pith, or the 

 pith and. primary wood, which ever may have existed ; the 

 second zone with longitudinal lines is the secondary wood. At 

 the sides are probably seen the bases of petioles; highly 

 enlarged. 



., 13. A root and rootlets, but whether or no of this organism it is 

 impossible to say; highly enlarged. 



,, 14. Horizontal section of a frond, prepared for the microscope, show- 

 ing on the right-hand side epidermal tissue, and on the left 

 dark brown patches between the veinules ; highly enlarged. 

 15. Longitudinal section of a frond, prepared for the microscope, 

 showing the upper and lower surfaces clothed with setiform 

 hairs, internal " tissue pillars," alternating with clear vacui- 

 ties, etc. ; highly enlarged. 



., IG. Cross section of a frond prepared for the microscope, showing 

 the form of the frond, its revolute margins ; and on the right- 

 hand side, filaments that may be pedicels for the support of 

 sporangia; highly enlarged. 



