B. FILICINEJE. 



ASPIDIUM FILIX-MAS (The Male Shield 

 Fern). 



A. MATURE SPOROPHORE. 



I. External Characters. 



I. Taking a well-grown plant of the common Male 

 Fern in summer, wash the soil away from the roots, and 

 observe the following external characters : 



A. The Stem is oblique and ascending. It is not 

 branched at its apex ; its surface is covered by the 

 persistent bases of the Leaves, which are densely 

 covered by numerous brown scaly hairs (Ramenta). 



B. The Leaves, the most prominent of which are 

 i. The fully-developed green leaves of the current 



year ; these are large and of complicated structure, 

 and the following parts may be recognised : 



a. A long almost cylindrical leaf-stalk which is 

 traversed by two longitudinal, lateral ridges or reduced 

 wings. This leaf-stalk supports 



1}. The numerous Pinnae, which are arranged in two 

 lateral rows, corresponding in position to the lateral 

 ridges above mentioned. Note that the arrangement of 

 the nerves in the segments of the pinnae is based upon 

 repeated bifurcation of the stronger nerves. On the 

 under side of the pinnae will frequently be found 



