NODDY TERN. 541 



most numerous of all the inhabitants of the Houtmann's 

 Abrolhos, breeding in prodigious numbers ; the bird lays 

 in November and December, forming a nest of sea-weed 

 about six inches in diameter, and varying in height from 

 four to eight inches, but without anything like regularity 

 of form ; the top is nearly flat, there being but a very 

 slight hollow to prevent the egg rolling off. The nests are so 

 completely plastered with their excrement, that at first sight 

 it appears to be almost the only material ; they are either 

 placed on the ground, in a clear open space, or on the tops 

 of the thick scrub, over the Sterna fuliginosa : these two 

 species incubate together in the utmost harmony, the 

 bushes to an immense extent wearing a mottled appearance, 

 from the great mass of birds of both species perched on the 

 top, the male Sterna fulignosa sitting quite close to the nest 

 of the Noddy, while its mate is beneath, performing her 

 arduous duties of incubation. On walking among these 

 birds' nests, I was surprised to observe the extreme tena- 

 city with which they kept their post ; in fact they would 

 not remove off the egg or young, but suffered themselves 

 to be fairly trod upon, or taken off by the hand ; and so 

 thickly were these nests placed, that it was no easy matter 

 to avoid crushing either birds or eggs at every step. In 

 the middle of January I found the eggs very nearly ready 

 to hatch, and but few young birds ; in numerous instances 

 the bird would suffer me to take it by the wing and throw 

 it off the nest, but would immediately return, although I 

 was still standing close to the spot. There would be an 

 overwhelming increase of this species yearly, but for one 

 check which nature has provided against it in the presence 

 of a lizard, which is extremely abundant about their breed- 

 ing-places, and which finds an easy prey in this and S. 

 fuliginosa. I am satisfied, from constant observation, that 

 on an average, not more than one out of every twenty birds 



