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, at 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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