534 



BOTANY 



PART II 



sporangia was still attached to the parent plant from which later the niacro- 

 sporophyll, together with its sporangium, separated as a whole. 



FIG. 505. Lyginodendron. Frond. (Sphenopteris Hoeninghousii.) (Reduced ^. After POTONI.) 



CLASS V 

 Pteridospermeae ( 132 ' 134 ) 



So far as our knowledge goes the Equisetinae, Sphenophyllinae, 

 and Lycopodinae are branches of the Pteridophyte stock which have 

 undergone no further development in the direction of the more highly 

 organised plants. From the Filicinae, on the other hand, the first 

 seed-plants had arisen even in palaeozoic times. These are the 

 Pteridospermeae, which stand on a higher level than all other 

 Pteridophytes and connect the Ferns with primitive Gymnosperms 



