252 WITH NATURE AND A CAMERA. 



change of sound. I asked the watchers (Darling 

 and Patterson) if they could account for this 

 strange behaviour, but, although they had often 

 noticed it, they were quite unable to suggest any 

 explanation. 



The summit of the Knoxes, a low island formed 

 partly of rock and partly of shingle and sand, is 

 occupied almost exclusively by Sandwich Terns. 

 When we visited it, most of the young birds had 

 been hatched off, and were either crouching 

 amongst the sand and shingle or running about, 

 according to their age and strength. They varied 

 much in colour, some being quite a dark buffish 

 brown, and others a light creamy grey. The 

 watchers assert that the down upon each chick's 

 back corresponds in coloration with the egg from 

 which it has been hatched. 



Of course, it was of no use attempting to test 

 this statement by comparing the colour of a young 

 bird lying beside an unhatched egg, because the 

 one afforded no manner of clue to the other, on 

 account of the fact that it is possible to find two 

 eggs in a Tern's nest as unlike each other as any 

 two in a thousand. I therefore only took the 

 evidence of such chicks as I could compare with 

 the shells they had just quitted, or were in the act 

 of emerging from, and must confess that they ex- 

 hibited a striking general resemblance of coloration. 



Many of these young ones were very difficult 

 to see, on account of their wonderful harmonisation 

 with the sand upon which they lay stretched 

 out flat as they could make themselves. In order 

 to show the protective value of their coloration, I got 

 my brother to make the studies appearing on the 

 opposite page. Of course, they are little more than 

 suggestive, on account of the localisation in a small 



