BOTANY 



and in place of precipitous scars the characteristic 'hopes' form a more 

 special feature. These branch out from the main dales and are narrower 

 valleys or ravines cut in the mountain sides by the burns or tributaries of 

 the main stream. In Kilhope, Welhope, Ireshope, and Burnhope the 

 main limestone crops out along the edge of the fells at from about 

 1,650 feet to 1,800 feet, and reaches an elevation of 1,800 feet in Bleak 

 Law. On the steep banks of Langdon Dale lines of limestone cliff stand 

 out conspicuously, reaching a height of 2,100 feet in Highfield above 

 the Grasshill lead-mines, from which it gradually declines towards 

 Newbiggin Moor. Here the limestone is exposed at 1,500 feet ; from 

 this point it rapidly descends, and at Egglestone is lost at a height of some 

 500 feet, disappearing also about the same elevation below Frosterley, on 

 the Wear. 



Many plants generally associated with the lowlands attain in the 

 Weardale ' hopes ' and in Harwood Dale an unusually high altitude, 

 and many reach their maximum limit in these limestone dales. 'Equisetum 

 palustre and Nephrodium dilatatum ascend to 2,100 feet on Highfield, and 

 the tway-blade [Listera ovatd) to 1,950 feet in Harwood Dale. The 

 whitlow grass [Erophila vulgaris), the prickly shield-fern [Aspulium 

 aculeatum), and the brittle bladder-fern {Cystopteris fragilis) are found at 

 1,800 feet on Kilhope and Bleak Law. On the southern slope of Kilhope 

 Law the moon wort {Botrychium Lunaria), Gentiana Amarella, the lady's 

 mantle {Alchetnilla vulgaris), and the water cress {Nasturtium officinale) 

 are interesting plants found at an elevation of 1,600 feet. Among other 

 plants peculiar to the limestone the following may be specially mentioned 

 at high elevations : — in Harwood Dale the moor-grass {Sesleria cceruUd), 

 the hairy rock-cress {Arabis hirsuta), Scabiosa columbaria, and the oat- 

 grass {Avena pratensis) ; the vernal sandwort {Arenaria verna), frequent 

 throughout the lead country on old lead-mine rubbish ; the stone black- 

 berry {Rubus saxatile) and the rock rose {Helianthemum vulgare) rejoicing 

 in the dry, exposed, rocky surfaces in Burnhope ; on Falcon Clints the 

 carline thistle [Carlina vulgaris), the mountain melic-grass {Melica nutans), 

 the spring gentian {Gentiana verna), and the smaller-flowered species 

 (G. Amarella) blooming later in the autumn, as well as the kidney vetch 

 {Anthyllis vulneraria) ascending to the plateau on Widdy Bank Fell. The 

 peculiarly rare yellow saxifrage {Saxifraga hirculus) grows in two places 

 in Ireshope at an altitude between 1,200 feet and 1,500 feet. This is a 

 greatly prized Durham species, being known in only two other localities 

 in England — north-west Yorkshire and Westmorland, and it is a plant 

 by no means easy to find. There are one or two stations in Scotland. 

 The alpine penny-cress (T'hlaspi alpestre) shows a curious preference for 

 the lead-mines throughout the district. The cranberry {Vaccinium Oxy- 

 coccus) is abundant on all the higher Teesdale and Weardale moors, 

 while the rare bog whortleberry {V. uliginosum) is found only sparingly 

 among the turfy bogs. The alpine variety of the scurvy grass {Cochlearia 

 officinalis) is also very frequent, and is carried down into the low country 

 along the streams. Several species of club-moss {Lycopodium) are widely 



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