278 THE COMMON TERN 



THE ARCTIC TERN 



STERNA MACRURA 



Bill slender, red throughout ; under plumage ash-grey ; tail much forked, 

 longer than the wings ; legs orange-red, in other respects very like the 

 last. Length fifteen inches. Eggs as in the last. 



This bird, as its name indicates, frequents high northern latitudes, 

 to which, however, it is not confined ; since in the Orkneys and 

 Hebrides it is the common species. It breeds also on the coast 

 of some of the northern English counties, but not farther south 

 than the Humber, though several instances are recorded of large 

 flocks making their appearance in different places at the season 

 when they were probably on their way from their winter quarters 

 — far away to the south — to their breeding-ground. In the 

 rocky islands, which they frequent from May to September, they 

 form colonies and lay their eggs, generally apart from the allied 

 species. The eggs closely resemble those of the Common Tern, 

 but are somewhat smaller. In its habits and general appearance 

 the Arctic Tern comes so close to the last-named species, that 

 the birds, even when flying together, can only be distinguished by 

 the most practised eye. 



THE COMMON TERN 



STERNA FLUVIATILIS 



Bill moderate, red with a black tip ; head and long feathers on the back of the 

 head black ; upper parts bluish ash ; quills ash-grey, brown at the tips ; 

 tail much forked, not longer than the wings, white, the two outer fea- 

 thers on each side dusky on the outer webs ; under parts white, tinged 

 with grey on the breast ; irides reddish brown ; feet coral-red. Young 

 birds have a good deal of white about the head, and the feathers on the 

 back are tipped with white ; tail ash-grey, wliitish at the tip. Length 

 fourteen inches. Eggs olive-brown, blotched and spotted with ash and 

 dusky. 



On those parts of the coast where the Common Tern is abundant, 

 no sea-bird is more likely to attract the notice of the visitor than 

 the Common Tern. It is less in size than any of the common species 

 of Gull, with which, however, it is often confounded by the unob- 

 servant. It is more lively and active in its motions, not ordinarily 

 flying in circles, but, if I may use the expression, ' rambling ' 

 through the air, frequently diverging to the right or left, and raising 

 or depressing itself at frequent intervals. These characters alone 

 are sufficient to distinguish the Tern from any of the Gulls; 

 but it presents yet more striking features. Its tail is elongated 

 and forked like that of the SwaUow, and from this character 

 rather than from its flight it is commonly known as the Sea 

 Swallow. Its mode of taking its prey is totally different from 



