22 



MORPHOLOGY OF GYMNOSPERMS 



The foliage of Heterangium and of Lyginodendron has been shown 

 to be of the Sphenopteris type, one of the great and heterogeneous 



Fig. 17. — Sphenopteris elegaris (probably foliage of Heteraugiutn Grievii): part of 

 frond; X§. — After Stur (7). 



frond genera of the Paleozoic, in general habit like A.splenium (82). 

 The foliage of Heterangium Grievii is probably Sphenopteris elegans, 

 the leaf being large and stalked, several times pinnately compound, 

 and with numerous small leaflets (fig. 17). Scott (24) describes 



