306 



FILICALES 



[CH. 



aceae and thalloid Liverworts^ is worthy of mention as one of 

 the many possible pitfalls to be avoided by the palaeobotanical 

 student. The long linear fronds of such genera as Vittaria and 

 Monogramme might well be identified in a fossil state as the 

 leaves of a grass-like Monocotyledon, or compared with the 



Fig. 236 h. Pteris aquilina. 



Leaf from the same plant grown out of doors, (i nat. size.) 

 After Boodle. 



foliage of Isoetes or Pilulana. The resemblance of some fern 

 leaves with reticulate venation to those of Dicotyledons has led 

 astray experienced palaeobotanists ; it is not only the anasto- 

 mosing venation in the leaves of several ferns that simulates 

 1 Goebel (05) ; Baker (67). 



