PAST HISTORIES OF PLANT FAMILIES 



131 



suggested that the male fructifications of the Bennettiteae 

 and the Pteridosperms show some Hkeness to the 

 Marattiaceae, but there does not seem much to support 

 any view of phylogenetic connection between them. 



Before leaving the palaeozoic ferns, mention should 

 be made of the very numerous leaf impressions which 





■Transverse Section of Stem of Psaronius 



V, Numerous irregularly-shaped steles; s, irregular patches of sclerenchyma ; /, leaf 

 trace going out as a horseshoe-shaped stele ; c, zone of cortex with numerous adventitious 

 roots r running through it ; sc. sclerized cortical zone of roots ; w, vascular strand of roots. 



seem to show true fern characters, though they have not 

 been connected with material showing their internal 

 structure. Among them it is rare to get impressions 

 with the soi'i or sporangia, but such are known and are 

 in themselves enough to prove the contention that true 

 ferns existed in the Palaeozoic epoch. For it might 

 be mentioned as a scientific curiosity, that after the 

 discovery that so many of the leaf impressions which had 

 always been supposed to be ferns, really belonged to 



