390 Fauna of Twizell. 



thrushes. Fieldfares frequently remain here till May is far ad- 

 vanced, a fact which long surprised me, as most of the species 

 which remain with us have ere then reared a full fledged brood. Mr 

 Hewitson, however, in his beautiful work on British Oology, sa- 

 tisfactorily accounts for so late an appearance, as he informs us 

 from actual observation that they do not commence nidification 

 in Norway, one of their breeding-stations, before the end of May ; 

 and further, that they differ from all their congeners in the re- 

 markable fact of breeding, like the rook, in large societies. The 

 dipper (Cin. aquaticus,) that lively attendant on our mountain 

 streams, and whose sweet and early carol enlivens the solitary 

 situations it frequents, breeds annually in Twizell Dean. The situa- 

 tion selected is the face of a rock or craggy steep overhanging the 

 water, and frequently in a spot where it might be expected to be 

 always saturated with wet from the dripping of the rock above, 

 yet so compact and well framed is the dome of the nest, that it shoots 

 off like a penthouse all superabundant moisture, and the eggs and 

 young remain dry and warm in their mossy and leaf-lined receptacle. 

 When the nest contains young, it is easily detected by their loud 

 chirping as often as the old birds fly past or approach the nest with 

 food. On quitting the nest, after feeding the young, the old birds 

 frequently drop into the water, dive, and rise at some distance, when 

 they take wing. I have before stated my opinion, that the dipper 

 does not walk at the bottom of the water when submerged, — a power 

 confidently attributed to it by various writers, — but uses the same 

 exertion in this act as other diving birds. This opinion is confirm- 

 ed by repeated observations, extending through a course of many 

 years, during which I have watched its habits with particular atten- 

 tion, and oft when the bird has been close to me, though unaware 

 of my near propinquity. The young, even before they leave the nest 

 of their own accord, if disturbed and made to quit it, dive instinc- 

 tively the moment they touch the water, but their progress beneath 

 the surface, which I have frequently seen extended to six or eight 

 yards, is always by the peculiar motion of the wings, made use of by 

 other diving birds, and never by walking at the bottom, — a feat they 

 ought to perform in common with their parents if given to them, 

 like the usual mode of diving, as a natural or instinctive habit. I 

 may also state that their internal anatomy presents nothing pecu- 

 liar, or that could give one reason to suppose that they were likely 

 to possess so extraordinary a power. Of the genus Salicaria, the 

 sedge warbler (Sal. phragmitis) is still frequent upon the margins 

 of the brooks and moist bushy situations; but the grasshopper 



