TEE COMPLETED ATOLL. 285 



the most numerously represented of which is what I believe 

 to be the Sterna hirundo. These frequent the island twice in 

 the year for the purpose of breeding. They rest on the 

 ground, making no nests, but selecting tufts of grass, where 

 such may be found, under which to lay their eggs. I have 

 seen acres of ground thus thickly covered by these birds, 

 whose numbers might be told by millions. Between the 

 breeding seasons they diminish considerably in numbers, 

 though they never entirely desert the island. They are expert 

 fishers and venture far out to sea in quest of prey. The 

 Noddies (Sterna stolida) are also very numerous. They are 

 black birds, somewhat larger than pigeons, with much longer 

 wings, and are very simple and stupid. They burrow holes 

 in the guano, in which they live and raise their young, gen- 

 erally inhabiting that part of the deposit which is shallow- 

 est and driest. Their numbers seem to be about the same 

 throughout the year. The Gannet and Booby, two closely 

 allied species (of the genus Sula), are represented by two or 

 three varieties. They are large birds, and great devourers 

 of fish, which they take very expertly, not only catching those 

 that leap out of the water, but diving beneath the surface 

 for them. They are very awkward and unwieldy on land, 

 and may be easily overtaken and captured, if indeed they at- 

 tempt to escape at all on the approach of man. They rest 

 on the trees wherever there is opportunity, but in these islands 

 they collect in great groups on the ground, where they lay 

 their eggs and raise their young. One variety, not very nu- 

 merous, has the habit of building 1 up a pile of twigs and 

 sticks, twenty or thirty inches in height, particularly on How- 

 lands, where more material of that sort is at hand, on which 

 they make their nest. When frightened, these birds dis- 

 gorge the contents of their stomachs, the capacity of which 



