THE POLYPODIES. 



which the fronds grow is about six inches. But 

 luxuriant specimens growing under favourable 

 conditions attain several inches more than that. 

 Most delicate and fragile are the frond-stems,, 

 which are generally as long again as the leafy 

 portion of the frond. 



The three-branched habit of this Fern, which is 

 so distinctly characteristic of it, is indicated in 

 the incipient stage of the frond's growth; for 

 each branch is then rolled up in a little ball. At 

 this stage, therefore, there is the curious appear- 

 ance of the stipes with three wire-like branches 

 at its top, having three little green balls at their 

 tips. When the three little balls have become 

 fully unfolded, the entire frond is broadly trian- 

 gular in shape. The branch in the centre of the 

 three is in a line with the continuation of the 

 main stem ; and at right angles with this branch 

 are the two lateral ones : there being a clear 

 space of stem between the point, where, a,t the 

 top of the stipes, the three branches unite, and 

 the commencement of the leafy portion of each 

 branch. The largest of the three branches is the 

 central or uppermost one. Each branch of the 



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