102 THE BIRDS OF YORKSHIRE. 



north-western Yorkshire ; it also occurs, but less numerously r 

 on the streams of the south-western moorlands, and is fairly 

 common in suitable haunts among the hills of Cleveland. 

 It breeds regularly by the side of streams near the coast 

 between Loftus and Staithes, and in severe weather has 

 been seen among the rocks on the sea-shore. In these 

 extensive habitats the three hundred feet contour line may 

 be taken as defining the lower limit of the bird's distribution 

 in any considerable abundance, while below this elevation 

 it is sporadic down to as low as one hundred feet. It is a 

 strictly sedentary species, but when frost of unusual severity 

 and long duration render its subalpine home untenable, 

 owing to the ice-bound streams no longer affording food, 

 the Dipper descends to the lower reaches, and even then 

 seldom indeed moves further than necessary, though it has 

 once or twice been known to visit the polluted waters of the 

 manufacturing districts. 



In the East Riding it is a very scarce species and is known 

 only in one or two localities ; it has bred at Stamford Bridge, 

 and has been met with near Pocklington, while a pair have 

 nested near Scampston annually for several years. The Rev. 

 F. O. Morris shot a bird at Nunburnholme on the loth of 

 January 1856, which may have belonged to the Scandinavian 

 form, next to be described, but it was not preserved. 



Amongst curious facts in the nidification of this species the 



following is related by Mr. Henry Smurthwaite of Richmond 



',\Zi)ol. 1859; P't fe^ 1 ;)- " The nest was placed at the extreme 



erid of a *Sah(i Martin's hole, which extended two feet in a 



; ^apKiov^rJiangin^^a stream, and the old bird was captured 



' on the nest,' which' contained five fresh eggs. Subsequently 



it was dug out and was found to resemble much in shape 



that of a Blackbird, but, as usual, was composed of moss 



thickly lined with oak leaves, the dome, however, being 



entirely wanting." Another remarkable case, where a pair 



of Sand Martins usurped the nest of a Dipper, is vouched 



for by Mr. Thomas Altham of Bashall Hall (see Sand Martin). 



A nest is described (Morris's Nat. 1855, p. 268-9), which was 



placed under a small railway bridge. Here five nests were 



