266 
ANIMAL INTELLIGENCE. 
CHAPTER X. 
BIRDS. 
Adequately to treat of the intelligence of birds a separate 
volume would be required ; here it must be enough to 
deal with this class as I shall afterwards deal with the 
Mammalia — namely, by giving an outline sketch of the 
more prominent features of their psychology. 
Memory. 
The memory of birds is well developed. Thus, although 
we are much in the dark on the whole subject of migration 
— so much so that I reserve its discussion with all the 
problems that this presents for a separate chapter in my 
next work — we may at least conclude that the return of 
the same pair of swallows every year to the same nest must 
be due to the animals remembering the precise locality of 
their nests. Again, Buckland gives an account of a pigeon 
which remembered the voice of its mistress after an 
absence of eighteen months ; 1 but I have not been able to 
1 Curiosities , &c., p. 126. Wilson also, in his American Ornithology , 
gives the folio wing sufficiently credible account of the memory of a crow: — 
‘ A gentleman who resided on t he Delaware, a few miles below Easron, had 
raised [reared] a crow, with whose tricks and society ho used frequently 
to amuse himself. This crow lived long in the family, but at length 
disappeared, having, as was then supposed, been shot by some vagrant 
gunner, or destroyed by accident. About eleven months after this, as 
the gentleman one morning, in company with several others, was stand- 
ing on the ri\er shore, a number of crows happened to pass by ; one of 
them left the flock, and flying directly towards the company, alighted 
on the gentleman’s shoulder, and began to gabble away with great 
volubility, as one long-absent friend naturally enough does on meeting 
another. On recovering from his surprise the gentleman instant ly 
recognised his old acquaintance, and endeavoured, by several civil but 
sly manoeuvres, to lay hold of him ; but the crow, not altogether relish- 
ing quite so much familiarity, having now had a taste of the sweets of 
