INTEODUCTION. XXVll 



nopus didyma, Linaria repens, Pyrus aucuparia, Cochlearia da- 

 nica, Frankenia lievis, Chelidonium majus, Valeriana dioica, 

 Verhascum nigrum. Some, however, there are that abound 

 more in the island than on the main, as Ligustrum vulgare 

 and Rubia peregrina. 



It might be concluded, from the extent of coast-line which 

 our insularity commands, that the Flora of the Isle of Wight 

 would be particularly rich in marine or littoral plants ; but, 

 though our sea-shores are not deficient in species interesting 

 from their beauty or rarity, the geological structure of the 

 greater part of the coast is unfavourable to their permanent 

 establishment. Along the whole southern shore from below 

 Sandown village to Eockin End, and from thence westward to 

 the Needles, the sea washes the feet of the cliifs or the banks 

 of slipped land at their base, on which alone it is possible for 

 any vegetation to fix itself. The chfi's, in most parts perpen- 

 dicular, can afford footing but to few plants, whose tenure, from 

 the crumbling nature of the rock, is very brief and precarious. 

 These therefore are mostly grasses, as Agrostis alba (which 

 fringes the cliffs at Shanklin), or such other small plants as can 

 cling longest to the treacherous soil, or find room to flourish 

 on the narrow water-worn ledges. The slipped banks beneath 

 the cliffs, composed of the debris of these last, and of the clays, 

 &c., of the lower greeusand, are hardly more stable, being con- 

 stantly in a state of change from the undermining action of the 

 waves and the percolation of landsprings, often charged with 

 iron, that issue from the face and bottom of the rocks above, 

 which, made more friable by the infiltration of water and the 

 disintegrating action of frost, fall from time to time in vast 

 masses, burying the vegetation at their feet to a considerable 

 depth beneath the ruins. The generally wet and tenacious 

 character of the soil composing these slipped banks is ill suited 

 to plants that love a dry, loose, sandy or pebbly beach, and 

 which would therefore be sought for in vain along the line of 

 coast we have been speaking of. The vegetation (in many 

 places very scanty) that covers these accumulated disruptions 

 is mainly derived from the rock above, whatever that may be, 

 and consequently varies with its geological character in differ- 

 ent parts along the entire line of coast, modified also, in some 

 measure, by the nature of the softer substratum, forced out from 



