PTERIDOPHYTES 91 
and hence is called the male gametophyte. The relatively 
large gametophyte, developed from the large spore, pro- 
duces the female gamete, and hence is the female gameto- 
phyte. Fertilization takes place in connection with the fe- 
male gametophyte, and the young sporophyte begins to 
grow where the oospore is formed. This condition of asex- 
ual spores and gametophytes is found among all the higher 
plants, the reduction of the gametophyte often becoming 
so great that it is not much more than a sex organ. Further- 
more, the large spore is sometimes retained in the sporan- 
gium, and develops the gametophyte, the oospore, and 
eventually the young sporophyte within itself. It is evi- 
dent that in such plants the gametophyte is very greatly 
. reduced from its condition in the lower ferns and the 
mosses. 
