CHAPTER XXIV. 



Ophioglossales (Fossil). 



The fossils hitherto classed with the Ophioglossales are not 

 such as afford any satisfactory evidence in regard to the past 

 history or phylogeny of the group. In the generalised class of 

 Palaeozoic ferns, the Botryopterideae, we find certain characters 

 suggesting comparison with recent members of the Ophioglos- 



FiG. 301. Rhacopteris ep., Ballycastle, Ireland. From a specimen in the 

 Manchester Museum. [M.S.] 



saceae, but no trustworthy records of these eusporangiate ferns 

 are furnished by the older plant-bearing strata. 



The genus Rhacopteris (fig. 301), characteristic of the Culm 

 flora, has been compared with Botrychium, but on grounds which 



