INTRODUCTION. 33 
form it may without impropriety be called the 
“caudex.” The common Polypody is‘ an example 
of this form of stem that may be found every day 
in the year, and in almost any locality: it climbs 
over rocks, stone walls, and trunks of trees, just in 
the same manner as ivy, and indeed attaching itself 
in the same way, by its fibrous roots. The beautiful 
_ Bristle Fern is another excellent example of this 
kind of caudex, as may be seen whenever this de- 
lightful fern is successfully cultivated. The other 
form of rhizomatous or rootlike caudex is exempli- 
fied in the Common Brakes: it is always clothed 
with a velvety pubescence or coating of hair, and 
is invariably concealed beneath the ground. All our 
Spleenworts exhibit the “cormus” form of trunk, the 
crown whence the fronds are developed being in- 
variably clothed with hair-like scales, The true 
trunk, or cormus proper, is strikingly illustrated in 
the Male Fern, and the Lady Ferns, each of which 
may be taken as a fair representative of a Tree Fern 
in miniature. 
The third portion of a Fern is the’ frond: this 
is something like a deciduous branch: it cannot, 
: : Ci) 
