PALLAS’ DIPPER. 
451 
distribution of birds, this genus being one of the twenty-five 
European, enumerated in our Ohservations^ as not known to 
turesque and sometimes solitary scenery by its clean and cheerful appearance, or 
associating more sedate recollections with the low and pensive melody of its 
song. They live generally in pairs, keeping entirely to the line of the brook ; 
and, in their flight, fly directly up or down, with a rapid motion of the wings, 
uttering a single monotonous alarm note, and when about to alight, fall, or splash 
as it were, in the stream, and swim to shore. Previous to the season of incu- 
bation, they become more noisy. The nest is formed exactly like that of the 
common wren, with a single entrance, and is composed of the ordinary mosses 
found near the stream, without much lining. It is generally placed under a pro- 
jecting rock, a few yards above the water, and often where a fall rushes over, 
in which situation the parent birds must dash through it to gain the nest, which 
they do with apparent facility, and even seem to enjoy it. At night they roost 
in similar situations, perched, with the head under the wing, on some little pro- 
jection, often so much leaning as to appear hanging with the back downwards. 
I r’ecollect a bridge over a rapid stream, which used to be a favourite nightly 
retreat, under the arch ; I have there seen four at a time sitting asleep in this 
manner, and used to take them with a light. Before settling for their nightly 
rest, they would sport in the pool beneath, chasing each other with their shrill and 
rapid cry, and at last suddenly mount to their perch ; when disturbed, they would 
return again in flve minutes. During winter, they migrate to the lower streams ; — 
flowing into the Annan, in Dumfriesshire, there are many Alpine tributary rivu- 
lets where these birds are abundant in summer ; during winter they remove 
almost entirely to the latter, where they find a more abundant supply of food, and 
their aquatic powers are more easily observed. On every reach one or two may 
be seen perched upon some projecting stone or stick, or watching by the very edge 
of the ice, whence they drop at once on their prey, consisting now almost en- 
tirely of the smaller fishes | when successful, they return to the edge and devour 
the spoil. They are most active in their motions during this occupation, and 
dive and return with such rapidity, as to seem constantly dipping and rising, 
or as perhaps better expressed by a quaint poet, it 
“ Comes and goes so quickly and so oft. 
As seems at once both under and aloft.” 
Inmailder weather, when the river was less choaked with ice, I have seen 
them swimming and diving in the centre of the pools, and so expertly, that I 
have mistaken and followed them for the little grebe. But in all their activity, 
I have never been able to see them walk upon the bottom, where the depth ex- 
ceeded a few inches, and I believe it is contrary to the habit of any aquatic bird ; 
the motion has been in all cases, like all others, performed by the wings. 
The species of the genus at present stand nominally as follows : The common 
