Mr. Winch on the Distribution of indigenous Plants. 51 



and geological researches. In accordance with this plan, my first ob- 

 ject will be to give a succinct description of the formations of rocky- 

 strata, and masses constituting the base of these counties, from the de- 

 bris of which the diluvial soil chiefly has its origin. 



From their antiquity, the crystalline rocks of Syenite, Greenstone, 

 Porphyry, and Amygdaloid, of which the Cheviot group of mountains are 

 composed, first lay claim to our attention. Whatever may have been the 

 origin of these unstratified masses, their having assumed their present 

 form at a very remote period cannot be doubted, for in places they are 

 traversed by veins of Granite, and rocks of Grauwacke and the Old Red 

 Sandstone rest upon them. Pitchstone has also been noticed among 

 these hills, but never detected in situ. Cheviot is 2658, and Hedgehope 

 2347 feet high, but, notwitstanding their elevation, these mountains are 

 not so propitious to the growth of rare plants as might be expected. 

 The southern botanist, however, would not overlook Saxifraga stellaris, 

 Carex rigida, Epilobium alsinifolium, Epilobium angustifolium ; and here 

 are our only localities for Cornus suecica, Carex laevigata, and Rhodiola 

 rosea, though the latter has been found on Fast Castle, and in abun- 

 dance, at the foot of a deep glen about a mile south of that spot, and 

 on rocks between Lamberton and Barmouth, on the coast of Berwick- 

 shire — another instance of an alpine species re-appearing on the sea 

 shore, common to a few other plants. 



The Encrinal, Mountain, or Carboniferous Limestone, a formation of 

 much greater extent and importance in every point of view, succeeds 

 the Porphyritic mountains ; it rises in the neighbourhood of Berwick, 

 and skirts the sea shore for thirty-five miles, till covered by the New- 

 castle coal strata near the mouth of the river Coquet ; if a line be 

 drawn from this point, so as to cross the Tyne at Bywell, the Derwent 

 near Allansford, the Wear below Wolsingham, and the Tees not far 

 above Pierce Bridge, its Eastern boundary will be tolerably well defi- 

 ned ; though the appearance of a stratum strongly resembling the Mill- 

 stone Grit, one of its members, at Berwick Hill, near Mason Dinning- 

 ton, might lead to the supposition of its intruding into the Coal-field, 

 in that part of the line, further than had been conjectured. Towards 



