122 THE GULLS 



markings are often almost obsolete. (PI. I.) Average size of 85 eggs, 2-3 x 1-6 in. 

 [58*5 x 41-6 mm.]. Nothing appears to be recorded as to the length of the incuba- 

 tion period in this species or the share of each parent, but probably it lasts for about 

 three weeks. The breeding season in Scotland begins as a rule about the second 

 week in May, sometimes a few days earlier, and though only one brood is reared, 

 second and third layings may be found fresh throughout May and June where the 

 birds are much harried. In more northerly situations, such as the Gulf of Bothnia 

 and northern Scandinavia, the eggs are often not laid till June. [F. c. n. J.] 



5. Food. The species is omnivorous. Worms, insects, crustaceans, 

 molluscs, fish (alive and dead), garbage, occasionally grain, small birds, and voles, 

 all form part of its dietary. The young are fed by both parents, probably on 

 worms, insects chiefly, but exact information is lacking. [F. B. K.] 



HERRING-GULL [Larus argentatus argentatus Pontoppidan ; Larus 

 argentatus Gmelin. Cob, silver-back, ladrum-gull (Devon), white-maa 

 (Shetlands). French, goeland argente ; German, Silber-Move ; Italian, 

 gabbiano reale nordica], 



i. Description. The adult herring-gull resembles the lesser blackbacked- 

 gull, but is at once distinguished by its larger size and the pearl-grey colour of the 

 back and wing-coverts, the flesh-coloured legs, and the yellow rim round the eyelid. 

 The sexes are alike, and there is a slight seasonal change of coloration. (PI. 105.) 

 Length 24 in. [609 '60 mm.]. As in the lesser blackbacked-gull, the scapulars, 

 secondaries, and primaries are tipped with white. The outermost primary differs 

 from that of the lesser blackbacked-gull in that the white area of the terminal por- 

 tion of the quill is much larger, and crossed by a narrow sub-apical bar of black, while 

 the penultimate feather is tipped white, and has a large white patch or " mirror " 

 some distance from the tip, and in the closed wing concealed by the tip of the 

 fourth primary. The innermost primaries are pearl-grey ; while the black area 

 gradually decreases in the outermost primaries from the first (outermost) to the 

 sixth, which has only a black spot near the tip of the outer web. After the autumn 

 moult, the crown and hind-neck are streaked with ash colour. The juvenile 

 plumage differs from that of the lesser blackbacked-gull in the markedly paler hue 

 of the ground-colour, and in that the white marginal areas are not of uniform width 

 but irregular, giving a more mottled appearance to the plumage. On the long inner 

 secondaries this marginal area of white forms a dentate pattern. The inner webs 

 of the inner primaries are much paler than in the young of L. fuscus, wherein all 



