(2190) Phaethon lepturus lepturus.
The White Tropic-bird.
Phaethon lepturus Daudin, Buff. Hist. Nat., xiv, p. 319 (1802) (Mauritius). Phaethon flavirostris. Blanf. & Oates, iv, p. 350.
Vernacular names. None recorded.
Description. Very similar to L. indicies but with the back pure unbarred white and having a much longer tail; the primaries are black with white tips and broad white inner webs, the white increasing until the seventh is all white; outermost secondaries pure white; innermost secondaries and scapulars black with broad white edges; inner least wing-coverts white, those next them black and the median and greater pure white; tail-feathers black-shafted.
Colours of soft parts. Iris brown; bill pale yellow; tarsi yellow, feet black.
Measurements. Wing 252 to 282 mm.; the central tail-feathers up to 575, generally about 450 mm.; tarsus 21 to 23 mm.; culmen 44 to 51 mm.
Young birds have the head, neck, upper parts and lesser wing-coverts barred with black, otherwise all white except the black eye-patch.
Nestling in down pure white.
Distribution. Red Sea and Persian Gulf, over the whole of the Indian Ocean. Breeding in Rodriguez and Mauritius.
Nidification. Similar to that of other species of Tropic-birds. Three eggs in my collection vary considerably. One is like an egg of Pernis, deep red with still deeper blotches; the second is similar but duller and with the blotching confined to the larger end; the third gives one the impression o£ a lilac-grey egg, the ground-colour dull pinkish, covered with freckles of grey-lavender and reddish and with a few scattered blotches of dark red here and there over the whole surface and in a deep ring round the larger end. They measure 56.4 x 39.1, 59.0 x 40.3 and 53.1 x 41.0 mm. The breeding-season is May, June and July, varying somewhat in different islands.
Habits. Those of the genus.