EXPRESSION IN THE ANIMAL EYE 
195 
of a word of commendation, while poets and painters 
have never tired of celebrating the dark eyes of their 
cousins, the roebuck and the gazelle. 
In birds the contrast is even more marked. As a 
rule, the eyes of the hawks are light-yellow, bright, 
and piercing, with wonderful powers of vision. The 
true falcons, which do not surpass the hawks either in 
size or courage, have black eyes, which lend a nobility 
and dignity to the expression of the bird which the 
goshawk, with all its pride of carriage, never attains. 
There is something infinitely roguish and mischievous 
in the light-blue eye of the jackdaw, which would 
be pure ruin to the character of its grave cousin 
“ parson ” rook, if, by some unkind freak of nature, 
one were born with such disfigurement; indeed, it 
may be doubted if the colony would not pronounce 
sentence of execution at once upon such a discredit 
to the tribe. There seems good reason to believe 
that this feature, often the only obvious mark which 
distinguishes young nestlings of one species from 
those of another, is that which leads to the detection 
and prompt destruction by birds of the newly-hatched 
young, from alien eggs which have been placed for 
experiment in their nests. There is, however, one 
middle shade found in birds’ eyes which is singularly 
beautiful, the so-called “ gravel-coloured ” eye of 
certain breeds of pigeon. This is really a brilliant 
shade of tawny-red, and though unshaded by lashes, 
and set in the centre of the bare “ cere,” gives to 
the birds a bold and intelligent appearance in com- 
