20 BRITISH BIRDS WITH THEIR NESTS AND EGGS. 



measures 2 inches by itf inch. A smaller and rounder egg measures i?g inch by 

 H4 inch, whilst an abnormally large . . . one reaches the dimensions of 21?, inches 

 by i^ inch." 



The male and female are alike, except that the latter is somewhat smaller 

 than the former, and has a slightly more slender bill. In the breeding season 

 the forehead, from the nostrils, over the top of the head to the level of the eye, 

 down to the nape of the neck, including the crest, jet black ; all the upper surface, 

 including the tail (whose outer feathers are whiter) pearl grey ; primaries (of which 

 the four outer are white shafted), when fresh moulted, pearl grey, but later in 

 the season the tips and inner webs darker ; " a distinct white wedge on the upper 

 part of the inner web of the outer primary, but smaller and less defined on the 

 succeeding flight feathers " (Saunders) ; lower half of the lores, sides of the face, 

 and the entire under surface of the body and wings, white ; bill black, sometimes 

 red at the base of the lower mandible ; iris brown ; legs and feet reddish-black, the 

 webs of the toes moderately indented. Length I4i;-i5i inches ; wing 12-13, or more 

 than twice the length of the tail, which is 5^-6, a character which distinguishes 

 this Tern from other species; as also the tarsus in being ij inch, or larger than 

 the middle toe and claw, which together measure ij inch. 



The eggs are intermediate in colouration between those of the Gulls and 

 Marsh-Terns, and provide another character, in addition to the form of the bill 

 and the habitat of the bird, indicating the intermediate position the Gull-billed 

 Tern holds between the Larina and the Stern inee. According to Mr. Seebohm, 

 whose enormous collection of eggs gave him a better opportunity than most 

 ornithologists for studying their various varieties, says that the ground colour is 

 a yellow ochre, or stone colour, of a lighter or darker shade, and occasionally a 

 pale greenish-brown, with small greenish, or reddish-brown, roundish spots or 

 irregular blotches, those underlying being paler and greyer (simply because they 

 are, as in all eggs, not on the surface, but underneath a thin layer of shell) ; as 

 a rule the markings are evenly distributed, or they may be more agglomerated 

 round the larger end. 



The eggs are lai'd about the beginning of June, and the young are mostly all 

 hatched before the end of July. The downy chicks are buy or stone-white, 

 mottled and striped with brown, or dark grey, on the top and sides of the head, 

 and along the back : the under side is uniform greyish-white. 



The fully fledged bird differs from the summer dress in having all the region 

 which is then black distinctly buff-tinted white, streaked with greyish-black on 

 the crown and mottled on the nape ; the eye set in a darker lozenge ; the upper 

 side, especially between the wings, distinctly fawn colour, deepening (in a week or 



