414 Relations between Geological Strata and 



cabbage, the rock roses, bloody crane's-bill, &c., Plantago 

 Coronopus, and P. maritima, Pyrus Theophrast/, fennel, &c., 

 are common equally to Orme's Head, Priestholm, and a part 

 of Anglesea, which lies exactly opposite these rocks, and forms 

 the continuation of the range of mountain limestone. When we 

 come to examine the line of greenstone which forms the rocks 

 of Caernarvonshire, we find not one trace of these luxuriant 

 and beautiful vegetables. 



This contrast is peculiarly striking at Beaumaris. A short 

 ride along the north shore of Anglesea, from the town, brings 

 you to the limestone range, with abundant traces of its plants ; 

 but on the south side of the town, the picturesque woods of 

 Baron Hill skirting the Menai, and forming shelter of every 

 kind for vegetables, there is not enough to reward even the 

 most enthusiastic botanist. The causes may be in the stratum, 

 which changes, near Beaumaris, from limestone to sienite and 

 trap. The walk from Orme's Head, along shore, towards 

 Abergele, affords a similar contrast. The mountain limestone 

 plants prevail more or less, according to situation, exposure, 

 and depth of soil, till you leave the range near Llandrillo ; and 

 then there appears a new and scanty range of vegetables, the 

 products of a sandstone range which crosses from * Llansant- 

 ireyd, and introduces to the sea-shore the same plants which 

 scantily adorn the Conway's bank about a mile above the 

 bridge. These are Glaux maritima, Silene maritima, and 

 Chelidonium Glaucium (the fetid celandine, or yellow horned 

 poppy), a singular but disagreeable plant, and forming a 

 strong contrast to the delicately tinted and fragrant Thymus, 

 marjoram, and milkworts you leave behind at the descent of 

 Pen bach. Convolvulus Soldanella (sea bindweed) is one of 

 the productions claimed by the greywacke formation of the 

 Penmonmawr mountains, and denied to the limestone of 

 Orme's Head. It is true that a few specimens may be en- 

 countered near Llandudno, but they are seldom seen in a 

 flowering state ; and I have never found one seed-vessel of that 

 species on the shore opposite the town of Conway, although 

 familiar to me from frequent search. The plant, however, 

 flowers and produces seed in great abundance, on the level 

 tract of shore subtending the cliffs of Penmonbach. It is 

 unnecessary to repeat, that the rocks on either shore are quite 

 different. 



During the month of July, 1828, I had an opportunity of 

 examining another mountain limestone district, St. Vincent's 

 Rock, and Clifton Downs, near Bristol. In company with a 



* Village of St. Friga, near Conway Bridge. 



