I 3 2 



ANCIENT PLANTS 



the seed-bearing Pteridosperms, there was a period of 

 panic among some botanists, who brought forward the 

 startling idea that there were no ferns at all in the 

 Palaeozoic periods, and that modern ferns were de- 

 generated seed-bearing plants! 



These two big groups from the Palaeozoic include 



practically all the ferns 

 that then flourished. 

 They have been spoken 

 of (together with a few 

 other types of which little 

 is known) as the Primo- 

 filices, a name which em- 

 phasizes their primitive 

 characters. As can be 

 seen by the complex or- 

 ganization of the genera, 

 however, they themselves 

 had advanced far beyond 

 their really primitive an- 

 cestors. There is clear 

 indication that the Bot- 

 ryopterideae were in a 

 period of change, what 

 might almost be termed 

 a condition of flux, and 

 that from their central 



Fig. 92. Impression of Palaeozoic Fern, showing typCS VariOUS families 



son on the pinnules. (Photo.) separated and special- 



ized. Behind the Botry- 



opterideae, however, we have no specimens to show us 

 the connection between them and the simpler groups 

 from which they must have sprung. From a detailed 

 comparative study of plant anatomy we can deduce some 

 of the essential characters of such ancestral plants, but 

 here the realm of fossil botany ceases, to give place to 

 theoretical speculation. As a fact, there is a deep abyss 

 between the ferns and the other families of the Ptericlo- 



