The fern $Dryopteris$ is:

Which of the following is a fossil pteridophyte?

The presence of ciliated antherozoids in $Dryopteris$ indicates:

The antherozoids of Dryopteris are .......

$Selaginella$ is heterosporous. It produces two types of spores. The microspore develops into microgametophyte and the megaspore develops into megagametophyte. With respect to gametophyte,which one statement is correct?

Development of embryo in $Selaginella$ is