6 



STETJCTUEE OP FEENS. 



In order to understand the descriptions and other allu- 

 sions to the different parts of the plants under considera- 

 tion, it will be necessary to devote a little attention to 

 their structure, and to explain the terms which it will be 

 impossible wholly to exclude. If accuracy is to be main- 

 tained, it is important that correct terms should be used, 

 and if the meaning of these terms are at first thoroughly 

 understood, the reader will experience no inconvenience 

 from their employment. It is a mistake to jump at the 

 conclusion that scientific terms are only necessary to the 

 rigidly scientific student, or that a popular wwk is most 

 satis hictorily performed from whence they are wholly ex- 

 cluded. If the meaning and application of such terms 

 are first made clear, their employment is manifestly an 

 advantage both to the reader and the writer. 



Those organs in ferns, which most persons would at 

 once call the leaves, and which resemble in many par- 

 ticulars the leaves of ordinary plants, are generally desig- 

 nated yro^ic/^. The chief distinction which it is necessary 

 for a popular purpose to indicate between a leaf and a 

 frond, as applied to ferns, is, that the latter bear at the 

 margin, or on their backs, the organs of fructification ; 

 that is, the seed is produced from some portion of their 

 surface. These fronds are traversed by veins, which are 

 usually forked, but diverse in their arrangement, some- 

 times parallel, and sometimes radiating. 



The fronds of ferns, as well as the leaves of many ordi- 

 nary plants, are borne on a stalk, to which the name of 

 stipe is applied. When, therefore, we write of the stipe 

 of a fern, we mean thereby what would be called the 



leaf-stalk " of a flowering plant. The stipes are attached 

 at their lower extremity, or grow from, a root-stock or 

 rhizome, which is all the stem our indigenous ferns possess. 

 In the large tree-ferns this stem is elongated in a trunk- 



