464 COENOPTERIDEAE [CH. 



sporangium has a pedicel, and three to eight sporangia are 

 attached to a common peduncle ; the walls of the sporangia are 

 at least two cell-layers in thickness and the annulus consists of 

 a band of thick- walled cells passing from the crest down each 

 side (figs. B and C), thus differing from the sporangia of Botryo- 

 pteris (fig. 319, D, F) in which the broad annulus is confined to 

 one side. 



It is practically certain that the fronds described by 

 Grand'Eury* as Schizopteris pinnata (fig. 309, E) and Schizo- 

 stachys frondosus represent respectively the sterile and fertile 



Fig. 320. Stauropteris oldhamia. (After Tansley. From a aeotion in Db Scott's 

 Collection, x 60.) 



leaves of Etapteris. Zeiller'' gives expression to this by substi- 

 tuting the generic name Zygopteris for Schizopteris, and we may 

 now speak of the leaves as Etapteris. Dr White' has referred 

 to a new genus, Brittsia, some impressions of pinnate fronds 

 from the Coal-Measures of Missouri which, as he points out, 

 bear a close resemblance to Schizopteris pinnata Grand'Eury 

 (fig. 309, E). No sporangia have been found; it is, however, 

 probable that Brittsia problematica represents fragments of a 



1 Grand'Eury (77) A. PI. xvii. 2 Renault and ZeiUer (88) A. 



» White (99) p. 97. ^ ' 



