128 BULLETIN 113, UNITED STATES NATIONAL MUSEUM. 



driven back by their parents, who keep a careful watch over them. 

 Mr. Finley (1907) says of their behaviors at this time : 



I soon discovered that their -greatest anxiety seemed to be to keep their 

 children crouching low in the nest so they would not run away and get lost 

 in the crowd. I saw one young gull start to run off through the reeds, but 

 he hadn't gone a yard before the mother dived at him with a blow that sent 

 him rolling. He got up dazed and started off in a new direction, but she 

 rapped him again on the head till he was glad to crouch down in the dry 

 reeds. 



The parents seemed to recognize their own chicks largely by location. Sev- 

 eral times I saw old birds pounce upon youngsters that were running about 

 and beat them unmercifully. It seemed to be as much the duty of a gull 

 mother to beat her neighbor's children if they didn't stay home as to whip 

 her own if they moved out of the nest, but often this would lead to a rough 

 and tumble fight among the old birds. Sometimes a young gull would start 

 to swim off in the water, but it never went far before it was pounced upon 

 and driven back shoreward. 



Plumages. — The young bird, when first hatched, is covered with 

 thick, soft down of plain, light colors to match its surroundings, 

 " light buff " to " cartridge buff," brightest on the head and breast; the 

 upper parts and throat are clouded or variegated with light grayish, 

 and the head is sparingly spotted with dull black. These colors fade 

 out to a dirty grayish white as the bird grows older. The juvenal 

 plumage is much like that of the herring gull; the head and under- 

 parts are dark and mottled, the dusky markings prevailing; the 

 upper parts are boldly mottled, each feather being broadly edged 

 with buffy white and centrally dusky. The first winter plumage, 

 which is acquired early in the fall by a partial molt of the body 

 feathers, is everywhere mottled with dusky, the underparts, es- 

 pecially the neck and breast, being tinged with cinnamon; the tail, 

 which in the young ring-billed gull is basally gray, and the primaries 

 are uniform brownish black and the bill is dark. This plumage is 

 worn for nearly a year or until the first postnuptial molt, when 

 the bird is a year old. This molt is complete, producing the second 

 winter plumage, which is more or less mottled with dusky, except 

 on the mantle, which now becomes more or less clear "gull gray." 

 The new primaries are nearly black, but with little or no white 

 tips ; the tail is white at the base, becoming dusky near the tip. The 

 bill becomes yellow at the. base, but the outer half remains dusky. 

 A partial prenuptial molt occurs during the latter part of the 

 winter or early spring in both old and young birds, producing 

 whiter heads and necks. 



A nearly adult winter plumage is acquired at the second post- 

 nuptial molt, when the bird is a little over 2 years old. At this 

 molt, which is complete, the black primaries with limited white 

 tips and the pure white tail, often subterminally marked with dusky, 

 are acquired; the bill becomes wholly yellow. Winter adults have 



