THE GREY WAGTAIL. 115 



and from having examined numerous specimens 

 of which the sex had been carefully ascertained 

 by dissection. 



The haunts of the Grey Wagtail are somewhat 

 different to those of its congeners. It affects 

 pools and streams, especially where there is a 

 good current, and may frequently be seen 

 perched upon boulders and mill-dams, where it 

 feeds upon the freshwater limpets (Ancylus 

 fluviatilis), and other small mollusca which are 

 found attached in such situations. 



The nest is generally placed not far from the 

 water, in some inequality of the bank, or crevice 

 of an overhanging rock. Upon a rugged moun- 

 tain stream in Northumberland some years 

 since, I daily observed a pair of these birds, 

 and derived much pleasure in watching their 

 building operations. It was some time before 

 I could discover the nest, so skilfully was it 

 concealed, for the birds had selected a crevice 

 in a rock which was much overgrown with moss, 

 and by constructing their nest entirely of this 

 moss, it would easily have escaped observation, 



