Wayside, Seaside, and Rock Ferns 



This fern is the Wall-rue, so-called because its 

 favourite home is old walls and because its leaves 

 resemble those of the garden rue. Its scientific name 

 is Asplenium Rutamuraria, the second part of which 

 simply means Wall-rue. All plants have two names ; 

 the first is the name of the genus, a group of plants 

 possessing many characters in common, while the 

 second is the name of the species, a subdivision of the 

 genus. Thus plants have generic and specific names, 

 which may be compared with the family and Christian 

 names which we have found it necessary to adopt, so 

 that we may be readily distinguished not only from our 

 neighbours, but also from the members of our own 

 family. 



The genus Asplenium (Greek, splene, the spleen), to 

 which the Wall-rue and six other ferns to be described 

 in this chapter belong, is so named because long ago it 

 was believed that a preparation made from the leaves of 

 some of its members was an excellent remedy for 

 diseases of the spleen. For this reason also they are all 

 popularly termed Spleen worts. Now, if we examine 

 carefully the sori on the back of the frond we shall dis- 

 cover the distinguishing mark of the Spleenworts. We 

 must not choose a frond too young or one too old. On 

 the first the sori may not yet have appeared, and on the 

 second they will have probably grown so close together 

 that we cannot separate out one sorus from the mass. 



Here is one on which the spores are not yet ripe. 

 The sori are now seen to be arranged in lines and 

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