X FILICINEyE LEPTOSPORANGIATAi 337 



of its cell walls. During this process it slowly straightens, 

 carrying between the distal portion of the lateral walls of the 

 sporangium, which remain attached to the free extremity, the 

 greater part of the spores. When straight, it continues to 

 evert, and this usually proceeds until the two ends of the 

 annulus nearly or quite meet, when with a sudden snap it 

 throws the spores violently away and returns to nearly its 

 normal position." 



Paraphyses, in the form of pointed hairs, often with a 

 glandular terminal cell, sometimes occur with the sporangia. 

 These in some Ferns, e.g. Aspidiinn filix-nias, are direct 

 outgrowths of the sporangium itself 



