63 



ruins, rooted deeply in the decaying mortar, and often accompany- 

 ing Asplenium Ruta-muraria and Trichomanes. Like other natural 

 importations from the south, it is found most abundantly in the 

 western maritime counties that receive the more direct flow of the 

 tide, and has progressed slowly towards the northern and central 

 parts of the kingdom ; in Scotland it has not yet traversed beyond 

 Perth, and is still regarded as a rare species ; while in Ireland its 

 copious distribution seems to indicate an earlier arrival. The fronds 

 are evergreen, the new ones making their appearance in May, and 

 at intervals throughout the summer: they vary considerably in 

 size according to situation, and our figure may be regarded as re- 

 presenting the medium, from three to five inches in length, but 

 where much exposed they are often not more than a third of this, 

 and in very sheltered places sometimes extend to eight or ten 

 inches. Some specimens sent from Teneriffe and Madeira mea- 

 sure more than a foot and a half, with a greater proportionate 

 breadth, that induced me at first to believe them of a different 

 species. It is, however, a fern that cannot be mistaken, and I am 

 informed that seedling plants, raised from the spores of these 

 giants, assumed the general aspect of those of British growth. The 

 general outline of the frond is varied from linear to linear-lanceo- 

 late, and the alternate segments are occasionally so far separated 

 by the extension of the rachis as to assume the character of pinnae, 

 especially where growing in the deeper fissures of rocks. The 

 whole of the under surface is densely clothed with brown, pointed, 

 imbricated scales, finely serrated on their margins, the outermost 

 of which extend beyond the margins of the segments and often 

 overlap them ; on the unexpanded fronds these scales are white 

 and silvery. The venation is not very readily iraced unless in the 

 young state of the frond, or by carefully removing the sori and 

 scales from the back of an old one, when they will be found to 

 accord with the description of them given under the generic cha- 

 racter. The sori are oblong; their disposition has been already 

 noticed, as well as the obscure nature of the indusium : the latter 

 organ, if we are justified in so terming it, is rendered unnecessary 

 as a protecting cover to the thecse, in consequence of the disposi- 

 tion of the scales ; which are arranged in regular series along each 

 side of the veins and venules, pointing outwards, and conceal the 

 sori by their broad bases, which completely overlap them in their 

 immature condition. 



The medicinal value of Ceterach has long been exploded by 

 European practitioners, though still believed in among those of 

 the East. It seems to have been the true Asplenium of the Greeks, 

 mentioned by Dioscorides and others, and which, according to 

 Vitruvius, annihilated the spleen of the Cretan swine that fed 

 upon it. 



