170 



COMMON CANADIAN WILD PLANTS. 



The secondary divisions (or first divisions of the pinna 1 ) arc the 

 jnnnules. The stem, as in the Polypody, and in fact in all our 

 Ferns which have a stem at all, is a rootstock or rhizome. But 

 here we miss the fruit- dots or sori, so conspicuous in our firht 

 example. In this case it will be found that 

 there is a continuous line of sporangia around 

 ' the margin of every one of the pinnules of 

 the frond, and that the edge of the pinnule 

 is reflexed so as to 

 cover the line of spore- 

 cases. Fig. 263 is a 

 very much magnified 

 view of one of the 

 lobes of a pwuiule, 



ifr. 2fi2. 



with the edge rolled back to show the sporangia. Some of the 

 sporangia are removed to show a line which runs across the ends 

 of the forking veins. To this the snorangia arc attached. The 

 veins, it will be seen, do not form ;i net-work, and so are free, as 



