THE GULL-BILLED TERN. 695 



GELOCHELIDON NILOTICA* 



436. Gelochelidon nilotica nilotica (Gm.)— THE GULL-BILLED 

 TERN. 



Sterna nilotica Gmelin, Syst. Nat., 1, ii, p. 606 (1789 — Egypt. Ex 



Hasselquist). 



Sterna Anglica Montagu, Suppl. Orn. Diet., text and fig. (1830 — Sussex, 



type in Brit. Mus.). 



Gelochelidon palustris Macgillivray, Man. Brit. Orn., 11, p. 237 (1842 — 



New name to replace anglica which is not suitable, as only rare visitor). 



Sterna anglica Montagu, Yarrell, in, p. 531 ; Saunders, p. 639. 



Description. — Adult male and female. Winter. — Fore-head white ; 

 crown and nape varying whitish ash-grey to greyer with or without 

 fine black sh aft -streaks ; back of neck whitish ; rest of upper-parts 

 ash-grey ; lores white slightly speckled black, round eyes and 

 streak behind eyes grey-black, feathers edged white ; whole under - 

 parts white ; tail-feathers as upper -parts but outer webs of outer 

 pair usually almost white ; primaries with outer webs and tips 

 pearl-grey, broad blackish line along shafts on inner webs (most 

 marked on outer feather, 

 washed pearl grey on rest 



but becoming blacker, J$%$IS^ 



as do tips, by wear), ^j^^^^m^ 



base of inner webs pale 

 grey extended towards 

 tips in a wedge ; pri- 

 mary-coverts pearl -grey ; 

 secondaries grey edged _l_ 



and tipped white ; all ' v ^ 



Wing- COVerts as Upper- BiU of the Gull .billed Tern (Gelortelidon n. nilotica.) 



parts. This plumage is 



acquired by complete moult July to Oct. Summer. — The body- 

 plumage is moulted Feb. -April ; birds in full winter plumage in Nov. 

 and Dec, but moulting wings and tail but not body have apparently 

 begun spring moult ; of examples examined, however, only one 

 was moulting wings and tail as late as Feb. Fore -head, crown, nape 

 extending on to back of neck ; upper part of lores and sides of head 

 to level of lower part of eye glossy greenish-black ; rest of sides of 

 head and whole under -parts white ; whole upper -parts and wing- 

 coverts and tail as winter but usually a slight shade darker. 



Nestling. — Completely covered with longish, soft down with 

 fine hair -like tips. Upper -parts varying buff to grey tinged buff, 

 fore -head uniform but rest of upper -parts streaked and spotted with 



* This name has been rejected because the feet are described as flesh 

 coloured. As the description is otherwise good and leaves no doubt as to 

 what is meant by nilotica, the lapsus of the colour of the feet must not be used 

 to reject the name. Numerous names would require alteration if one lapsus in 

 an otherwise undoubted description was allowed to influence their recog- 

 nition. — E.H. 



