Initially it was still thought that they were `` transitional fossils '' intermediate between the ferns and cycads , and especially in the English-speaking world they were referred to as `` seed ferns '' or `` pteridosperms '' .
Initially it was still thought that they were intermediate between the ferns and cycads , and especially in the English-speaking world they were referred to as `` seed ferns '' or `` pteridosperms '' .