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MORPHOLOGY 
which becomes hard at maturity, forming a small nutlike body called 
the sporocarp (fig. 396). In Salviniaceae, therefore, the sporocarp is a 
sorus invested by an indusium. Microsporangia and megasporangia 
400 399 
FIGS. 399, 400. Azotta: 399, young sporocarp, showing a young megasporangium 
and the developing indusium; the megasporangium has advanced to the cutting off of 
tapetal cells (/); 400, megasporocarp, showing the terminal megasporangium with one 
megaspore (m) surviving the degeneration of he others, and the microsporangia (me) 
checked. After Miss PFEIFFER. 
begin to develop in each sorus, but only one kind matures, so that at 
maturity there are two kinds of sporocarps (megasporocarps and 
micros porocar ps, fig. 398), both kinds occurring on the same plant 
and even on the same leaf segment. All the sporangia have long 
