384. Proceedings of the Royal Physical Society. 
face of the rock on which it was to rest with a thick bed of 
well-matted hypnum and grass. The same materials were 
pressed into the inequalities of the rock which the back 
of the nest touched. The birds built and carried in turns. 
When the female was dropping the eggs, the male, as 
observed on one occasion, took up his abode in the other 
division. The birds were not so shy as I have often seen 
the species to be. They continued working while I must 
have been in full view of them. 
After the nest was removed, they began to build again 
on the same spot, but with less ambition. A single nest 
was begun in the centre of the spot before occupied by the 
double one. They had not, however, proceeded far with the 
work when it was given up ; and they ceased for a time to 
visit the stream at this point. 
The instance now referred to is the only one in which I have 
noticed such a wide departure from the usual mode of nest- 
building. It is, indeed, not uncommon for this bird to dis- 
pense with the roofing of the nest, when, as in rock crevices, 
it can obtain a natural covering. Even these, however, are 
exceptional cases. 
The dipper is generally said to perch only on stones, but 
I have several times seen it resting on the low branches of 
trees overhanging the water. Most observers assert that it 
never feeds on small fishes, but I have found small min- 
nows, and in one case the fragments of a stickleback, in 
its stomach, as well as gyrini, the larvse of 'phryganeoe, &c. 
The dipper's pretty and lively song may sometimes be heard 
even in severe winter weather. Dr J. A. Smith informs me 
that he once heard a dipper singing as it floated down the 
river Tweed perched on a mass of ice. 
