306 The Bird 
Let us glance at one more bird upon her nest,—a Laugh- 
ing Gull. At a distance we see a shapeless blotch of white 
sand among the reeds, that is all. We walk over a hundred 
other similar patches; but when near enough, we at 
last are able to distinguish the dark head and wing-tips, 
all but invisible among the shadows, and even through 
the centre of the head we can see two spots of light be- 
yond,—or no, it is the little subtle ring of white about 
the eye! 
Two majestic Black-necked Swans may swim closely 
along in full view near the opposite bank of a pond, and 
yet be totally unrecognizable; showing to the eye as 
bodiless necks or neckless bodies, according to the chang- 
ing conditions of light and shade around them. 
We see a troop of ostriches rushing past. Surely 
nothing could hide birds such as these! Again we see 
one of these birds prone upon the ground, and a mighty 
creature towering eight feet or more above the earth, 
becomes naught but a dark ant-hill, which the photo- 
graph picks out clearly, but which in the desert, dotted 
with ant-hills, would seldom be noticed even by the hungri- 
est of lions. 
Of course, like most other theories, this of protective 
coloration can easily be carried too far, but there are 
hundreds of instances where it seems to answer every 
requirement of the case. Few fields offer such opportuni- 
ties for original work of the most delightful character. 
As one example out of untold numbers, what explanation 
can we give of the Blood-breasted Pigeon or Bleeding- 
heart Pigeon, which, as its name denotes, has a splash 
