336 
OSMUNDACEiE. 
they soon become more lax and diffuse, and at last entirely lose 
their rigid compressed appearance. 
The barren frond differs in having the leafy portion continued 
to the very apex, where it terminates much as in the true ferns. 
The venation in a barren pinnule is shown at page 333, where 
it will be seen that the lateral veins branch alternately from the 
midvein, soon after leaving which, each is forked, and one or both 
of the branches are usually again divided, and all the branches 
run in parallel lines to the extreme margin of the pinnules. 
