364 THE ZOOLOGIST. 
on their eggs, but let the sun hatch them out. We found there 
was more truth in the theory than was at all pleasant. We had 
a succession of blazing hot days, and however carefully we con- 
cealed the camera, its presence near the nest seemed quite 
enough to decide the bird to let the sun do its work; this was 
notwithstanding the fact that they had all reached the last stages 
of incubation, when most birds sit closely. 
The two species probably nest in separate colonies because 
they do not agree together. On one occasion I had an instance 
of this whilst trying to photograph the Lesser Tern. A Common 
Tern alighted about ten feet to seaward of the nest, and stood 
there calling. Then it was joined by its mate, which settled 
down as if on eggs. Presently the standing bird waddled up to 
my Lesser Tern’s nest which contained a dead and a live chick, 
and, standing over them, shouted to the Terns overhead. Then 
it picked up one of the chicks—I thought it was the dead one— 
and dropped it; then it picked it up again and walked two or 
three feet away, and dropped it again. This time I could see 
it was the live chick struggling on its back. Then it picked it 
up, and, flying into the air, pitched about fifteen yards to sea- 
ward. I was so enraged at seeing my last chance of photo- 
graphing the Lesser Tern destroyed that, instead of photograph- 
ing this unique incident, I pursued the marauder, and after a 
little search found the chick uninjured, and the spot where the 
Common Tern had been sitting hollowed out as if she had been 
about to lay. The Lesser Terns did not come down to their 
nest, nor did they show any fight during the raid. 
Two years ago I saw a good deal of the Arctic Tern in the 
Hebrides, and, after watching the Common Tern for a fortnight, 
have come to the conclusion that it is possible to distinguish 
them when flying. The Common Tern has a much less jerky 
flight than the Arctic, and hovers in fishing a great deal more 
than does the Arctic; in fact, it more nearly approaches the 
Kestrel than any other bird I have yet watched in this respect. 
A third distinction which Cringle pointed out but which I 
cannot confirm, owing to not remembering how the Arctic Terns 
carry their tails, is that the Arctic Tern more often carries its 
tail closed than does the Common. This, I presume, accords 
with their different styles of flight, as I have noticed in calm 
