XXVIl] 



LESLEYA 



517 



represented in fig. 346 : the curled lobes may have originally 

 borne seeds. In the Brazilian examples the abruptly truncated 

 lobes " bear evidence of separation from reproductive bodies." 

 An important point is the association of these scale-leaves with 

 Gangamopteris fronds and with gymnospermous seeds of the 

 Samaropsis type. On the leaves assigned to Derhyella aurita 

 circular depressions occur at the base of the lobes which are 

 described as probably due to sporangia. 



Dr White's discovery gives us increased confidence in 

 expressing the view that Gangamopteris bore its reproductive 

 organs on specialised leaves very different from the sterile 

 fronds; it also strengthens the suspicion that the genus is a 

 member of the class of seed-bearing fern-like plants. 



Fig. 346. Arheria sp. ( = Noegyerathiopsis of Feistmantel). (Nat. size. After 

 Feistmantel. ) 



Lesleya. 



This generic designation was instituted by Lesquereux^ for 

 simple oval-linear leaves from the Coal-Measures of Penn- 

 sylvania. The leaves so named are probably generically 

 identical with the specimen doubtfully assigned by Brongniart^ 

 to the Coal-Measures, and made by him the type of the genus 

 Cannophyllites on the ground of a resemblance to the leaves of 

 the recent flowering plant Canna. Fig. 347 illustrates the 

 form of a Lesleya leaf from the Coal-basin of Gard, named by 



1 Lesquereux (W) A. p. 142 ; PI. xxv. 



2 Brongniart (28) A. p. 129. 



