62 0XYCH1UM. 



sori are soon confluent, and the free margin of the two indusia 

 wrap over the midrib, and the sori eventually covers the 

 whole disc, as in the Achrosticums. It is distinguished from 

 Lomaria in the sporangia being seated in the immediate axis 

 of the indusium, (in which respect it resembles Pteris,) whilst 

 in Lomaria the receptacle is broad, and occupies a great 

 portion of the space between the midrib and the axis of the 

 indusium. 



