Wayside, Seaside, and Rock Ferns 



the least of British ferns in height, it is remarkable for 

 the very large number of leafstalks springing from the 

 tufted rootstock. The striking resemblance of this 

 fern to the Buckthorn Plantain found on seaside rocks 

 has often been commented on. It is named Asplenium 

 septentrionale. The specific name, which means 

 " northern," refers to the fact that it is more frequent 

 in the north than in the south. 



One other fern, one of the commonest of British 

 ferns, we are sure to have growing on our old wall. 

 This fern is the Common Polypody, which is so very 

 distinct from all other native species that we have no 

 difficulty in at once recognising it. Its fronds, which 

 vary in length from 6 to 16 inches, are at first upright, 

 but, as they grow older, they assume a hanging posi- 

 tion. They are cut in a pinnatifid manner, the segments 

 growing smaller and closer as they reach the tips of the 

 fronds. Each segment is generally rounded at its 

 extremity, and may or may not be slightly toothed. 



Examining the back of the frond, we find the spore 

 cases of a golden-brown colour disposed in circular 

 clusters along both sides of the midribs of the segments. 

 The sori never have indusia, or coverings. This absence 

 of indusia, taken along with the circular or globular 

 sori, is the distinguishing mark of all the Polypodies. 



The rootstock is stout and creeping, and in its early 



stages is covered with scales. From this creeping 



stem leaves and roots are given off, but the leaves do 



not grow in tufts at its extremity, but spring alternately 



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