X. 
MAGNESIAN LIMESTONE. 
External Configuration. — One of the most remarkable features 
in Yorkshire, is formed by the long low terrace which runs in a straight 
line from the Tees at Pierse Bridge to the southern border of the County 
at Anston. The highest point in this range is Ledston Beacon, only 
450 feet above the sea ; the terrace breaks off abruptly to the west, and 
slopes very gradually below the central vale to the east. The rivers 
Tees, Yore, Nid, Wharfe, Aire, and Dun, all break through the range 
in pleasing and romantic glens, often enriched by wood, and unusual 
sinuosities of the stream. 
Internal Structure. — Generally beds of yellow magnesian lime- 
stone form the higher surface, margined by soft subjacent sandstones on 
the west, and by red gypseous clays and a purer limestone rock on the 
east. 
Aspect of Vegetation. — The hills are generally bare, and the soil 
is usually found to be infertile ; it yields coarse grasses and rough 
pastures ; but the Botanist may be consoled by many rare plants which 
belong to the range. 
DISTRIBUTION OF PARTICULAR PLANTS. 
The following species of plants have been found in no other district 
of Yorkshire. 
Anemone pulsatilla 
Asperula cynanchica 
Campannla rapunculoides 
Campanula patula 
Conyza squarrosa 
Ophrys aranifera 
Of these. Anemone pulsatilla, Campanula rapunculoides, and 
Campanula patula, are supposed to attain their northern limit in 
Yorkshire. 
Thorp Arch. — A very interesting and picturesque locality in this 
district ; will repay alike the Botanist, Entomologist, and Conchologist 
for a day’s close research in the woods and rocks which overhang the 
Wharfe. 
