90 HORSETAILS AND CLUB MOSSES 



cell it divides to form the embryo sporophyte with a suspen- 

 sor as in the higher plants. The embryo is parasitic on the 

 gametophyte for a long time finally, however, becoming 

 independent. 



Selaginella a higher branch of the Lycopodiales is hetero- 

 sporous. Some sporophylls produce only megasporangia 

 with megaspores, other sporophylls form only microsporangia 

 with microspores. The microspores develop into small simple 

 male gametes which bear a single antheridium with biciliated 

 sperms. The megaspores develop into minute female 

 gametophytes which bear archegonia. 



