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distinct glimmerings of Osmundaceous characters, 

 which at a hiter period became individiiahsed in 

 the direct ancestors of the modern forms. Our 

 knowledge of the past history of the Osmnnda famil}^ 

 has recently been considerably extended and })laced 

 on a firmer basis by the researches of I)r Kidston 

 and Professor Gwynne-Yaughan. These authors have 

 recognised in some exceptionally well-preserved fern- 

 stems from Permian rocks in Russia, anatomical 

 features which point unmistakably to close rela- 

 tionship Avith the recent members of the family (47) (48). 



Passing higher up the geological series, fertile 

 fern fronds with spore-capsules and spores practically 

 identical with those of Osmnnda have been found in 

 the Jurassic plant-beds of Yorkshire and in rocks 

 of approximately the same age in many parts of the 

 world. From Jurassic strata in New Zealand a 

 petrified fern-stem has been described (OsmuudUes 

 Dnnlo}ji), almost identical in structure with the 

 surviving species. Cretaceous and Tertiary examples 

 of similar ferns might be cpioted ; but enough lias 

 been said to establish the claim of the Royal Fern 

 and other members of the Osmunda-family to an 

 ancestry which possibly extends even farther back 

 than that of any other existing family of Ferns. 



A brief reference may be made to another fern now 

 represented by several species widely disseminated 

 in tropical and sub-tropical countries. The genus 



