146 PLANT-LIFE 



The expanded leaves are very handsome; they grow to 

 a length of from 2 to 3 feet, and form a circular tuft. 

 It is usual to call the leaves of Ferns " fronds." In the 

 Male Fern they are " compound," which means that the 

 leaf -blade is divided into what appear to be many leaves, 

 but are really leaflets. The leaflets of Ferns are called 

 finncs (L. pinna, a feather), and the frond of the Male 

 Fern is pinnate (shaped like a feather), the pinnae forming 

 two rows, one on either side of a stalk, termed the racJiis 

 (Gr. rachis, the spine). The pinnae themselves are deeply 

 lobed — pinnatifid — and in some specimens they are 

 completely pinnate, in which event the frond is described 

 as bipinnate. Two further points are worthy of remark 

 in regard to the leaves ; they taper to a point at the apex, 

 and the pinnae become shorter towards the base; again, 

 the rachis, like the main stalk, is furnished with brown 

 chaffy scales or hairs, which even extend to the veins 

 of the pinnae. In the mature plant the roots are all 

 " adventitious," or casual; they proceed from the bases 

 of the leaves: the main root developed by the embryo 

 always disappears at an early stage of growth. 



Such are the general external characters of the Male 

 Fern. If we examine well-grown fronds in the late 

 summer or autumn, we shall find brown sori, clusters of 

 sporangia, arranged as in Fig. 44, B, on the under 

 surface or back of the pinnae; they are numerous over 

 about two-thirds the length of the frond, but do not as 

 a rule appear at its base ; if they do so appear, they are 

 scattered and not regular in arrangement, as on the 

 higher part of the leaf. Close examination will disclose 

 the fact that each cluster of sporangia — i.e., each sorus — 

 is protected by a membrane, which, in our subject, is 



