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UPPER NIDDERDALE AND ITS FAUNA. 



W. EAGLE CLARKE, F.L.S., M.B.O.U., Leeds. 

 W. DENIS0N ROEBUCK, F.L.S., Leeds. 

 WILLIAM STOREY, Pateley Bridge. 



In view of the forthcoming visit of the Yorkshire Naturalists' Union to Upper Nidderdale, the 

 following account of it from a zoological point of view will not be without interest. 



Upper Nidderdale shares with Upper Swaledale the character of 

 being the most unsophisticated, the most secluded and sequestered 

 of the Yorkshire dales, and in each case the cause is the same. 

 Closed in at the dale-head by a long and semicircular sweep of moun- 

 tain wall which for nearly forty miles attains a continuous and un- 

 broken elevation of more than a thousand feet, and on Great Whern- 

 side reaches its maximum altitude of 2,310 feet, the dale is clearly 

 and sharply cut off from the neighbouring areas by a physical barrier 

 which, far from easy to traverse in summer, becomes practically im- 

 passable in the winter. As a natural consequence of their isolation 

 from this cause, the people of the dale retain to a greater extent than 

 elsewhere their primitive manners and customs, their vernacular 

 speech, and their old-world superstitions. The fauna and flora of the 

 dale, too, are more secure here than elsewhere from the inroads of 

 the vandals and philistines at whose hands the districts which are 

 more easily reached by railway have suffered to so large — not to say 

 alarming — an extent, and consequently retain their native luxuriance 

 and -variety to an unusual degree. 



The total drainage area or catchment basin of the river Nidd, from 

 its origin on the flank of Great Whernside to its junction with the Ouse 

 at Nun Monkton, is given at 260 square miles. Of this, however, what 

 is called i Nidderdale' covers only about a hundred square miles, 

 and may be said to terminate at about Ripley, where the hills rapidly 

 decline and the basin of Nidd becomes merged in that of its main 

 stream. Eastward of Ripley the many windings of the river, whether 

 it flows beneath the historic castle of Knaresborough or meanders 

 lazily through the pleasant meadows of Ribston, past the gigantic old 

 oak of Cowthorpe and by the once blood-stained field of Marston 

 Moor, are through the level alluvial flats of the great central plain or 

 vale of York. 



The physical configuration of the dale shares the general uniformity 

 of its geological structure, which is for the most part millstone grit, 

 except for the very limited tracts where the most easterly outcrops of 



July 1886. O 



