 The sporocarps are functionally and developmentally modified leaflets , although they have much shorter stalks than the vegetative leaflets . Inside the sporocarp , the modified leaflets bear several sori , each of which consists of several sporangia covered by a thin hood of tissue ( the indusium ) . Each sorus includes a mix of two types of sporangium , each type producing only one of two kinds of spores . Toward the center of each sorus and developing first are the megasporangia , each of which will produce a single large female megaspore . Surrounding them at the edge of the sorus and developing later are the microsporangia , each of which will produce many small male microspores . 
