AMERICAN FERN JOURNAL ll 
Because of the many striking resemblances to ferns, 
it is believed that these “seed ferns,’”’ or pteridosperms, 
as they are called, were directly descended from plants 
ancestral also to the true ferns. The cyeads or “fern 
palms” of our modern tropics, commonly included in 
the group Gymnosperme,'are generally recognized as 
descendants of the pteridosperms. This opens up a 
new line of fern allies, nearer at least than Equisetum 
and Lycopodium. 
But a still greater line of “allies” will have to be 
recognized if recent researches of G. R. Wieland on 
Mexican eycads are confirmed. He has found among _ 
certain Mesozoic cyeads a type of floral structure so 
much like certain modern angiospermous types that he - 
has concluded that our common flowering plants must 
_ be descended from the cycad-fern line. 
No one, however, is likely to include flowering plants 
under the title of fern allies. This name may be Lies a 2 
applied to three modern groups of plants, the 
Ophioglossales, the Salviniacee and the Mateibineos 2 
_the last two groups being often grouped together as_ 
_ the Hydropterides, or water ferns, but now. oes® 
__ Be related to separate lines of ferns. eee a 
