640 NODDY TERN. 



size and is built of dry grass, bits of sea-weed, twigs, fish-bones &c., 

 not interwoven but laid in a heap, with merely a slight cavity for 

 the egg. The top of a cocoa-nut tree or the outer branches of 

 mangroves are often selected, while in some places the nests are 

 on shelving rocks beneath overhanging cliffs, and, more rarely, on 

 patches of sand or grassy slopes. Audubon, who is responsible for 

 the statement that the Sooty Tern habitually lays three eggs, also 

 asserts that the complement is the same in the case of the Noddy, 

 but other observers in all parts of the tropics are unanimous in 

 stating that this species never has more than one. The shell has a 

 somewhat dull and rough surface, and is ruddy-white or buff in 

 colour, sparsely blotched and freckled with reddish-brown : average 

 measurements. 2 by i"4 in. The yolk is bright yellow, whereas in 

 the egg of the Sooty Tern it is deep orange-red. In the northern 

 hemisphere breeding takes place in May or June, but in the southern 

 tropic there is great irregularity, and fresh eggs may be found from 

 September to January. As soon as the young are able to fly the 

 birds disperse over the ocean, and when fatigued they frequently 

 settle on vessels, exhibiting a stupidity or indifference which has 

 procured for this species its trivial as well as its scientific name. 

 The food consists of small fish, molluscs, medusae &c. 



The adult has the forehead and crown grey, and the upper parts 

 sooty-brown, rather darker on the wings ; there is, however, some 

 difference in the above tints according to season, locality and the 

 age of the individual. Mature specimens soon after the moult are 

 nearly black on the lores and throat, while in younger birds those 

 parts are paler ; the under parts are browner than the back ; the 

 bill is black ; and the legs and feet are reddish-brown, with full 

 webs, which are yellowish in life. Length 16 in., wing 11 in. The 

 young bird has the forehead white, slightly speckled with brown, 

 while both upper and under parts are dull umber. In this and 

 other members of the genus the tail is graduated — not forked, the 

 central tail-feathers being the longest. Two smaller and quite 

 distinct species of Noddy are also found within the tropics ; while 

 in Polynesian and Australian waters there are yet two others, very 

 closely related, but characterized by their nearly uniform grey colour 

 and still smaller size. 



Owing to a practical joke, which afterwards became a fraud, 

 Thompson was led to include the Swift Tern, S. hergii of Lichten- 

 stein {S. velox of Riippell) in his ' Birds of Ireland ' ; it is a purely 

 tropical species. 



