Birds of Celebes: Laridae. 
897 
would appear that the species is not rare. We suppose it to he a resident, as 
a number of specimens were collected by Meyer at the Togian Islands in 
August, and the bird breeds in India — except the Central and Southern parts 
of the country, ■ — and in Australia. Mr. Saunders makes mention of some 
appreciable racial differences in this species; these are: slightly smaller size in 
India, a darker hue in the resident birds of S. Africa, a tendency to paler tints 
in Australia. 
The members of the genus Hydrochelidon may be distinguished from the 
other Terns by their toes being only slightly webbed — not more so, in tact, 
than in such a bird as Phalarojms, and Naumann remarks of the present 
species that it is hardly ever to be seen swimming, and, even then, there is 
no forward paddling, as the bird simply rests a little upon the .water. The 
web connecting the outer toe, which is the larger web, is indented almost as 
far down as the distal end of the first joint of the middle toe, the other web 
is considerably shorter. Four species of Hydrochelidon are admitted by Mr. 
Saunders Catalogue of Birds 1896, XXV, Gaviae). The Whiskered Tern may 
be distinguished from its three allies in winter by its larger size, further from 
H. leucoptera by its grey tail forked to a depth of about 2 cm, and from H. nigra 
by its larger feet. The fourth species is the American form of H. nigra, 
II. surinamensis. In its summer plumage II. hybrida is very different from them. 
As Naumann remarks, this species by its size, form, colour, markings and to some 
extent even in its habits stands midway between the Common Tern, Sterna 
hirundo and II. nigra. 
GENUS STERNA L. 
In the true Terns the feet are somewhat small, with the anterior toes 
webbed not quite to their ends, the middle toe and claw longer than, or equal 
to, the tarsus; the tail forked, more or less deeply; the wing long, more than 
twice the length of the secondaries; the first primary the longest; more or less 
of the head black in the breeding season, in one species this colour being 
reduced to a black transocular streak. Food: fish, caught by plunging. 
Mr. H. Saunders (1896) describes 33 species, of cosmopolitan distribution. 
382. STERNA MEDIA Horsf. 
Lesser Yellow-billed Tern. 
Sterna media (1) Horsf., Tr. L. Soc. 1821, XHI, 199; (2) Finsch & Hartl., Vog. Ost- 
Afr. 1870, 830; (3) Heiiglin, Orn. N.-O. Afr. 1871, 1430; (4) Salvad., Oat. Ucc. 
Borneo 1874, 377; (5) Saund., P. Z. S. 1876, 655; (VI) Dress., B. Einope YHI, 
285, pi. 583 (1878); (7) Legge, B. Ceylon 1880, 1030; (8) Salvad., Orn. Pap. 
1882, III, 437; (9) W. Bias., J. f. O. 1883, 129, 140; (10) Oates, B. Br. Bnrmah 
1883, n, 426; (11) Bams., Tab. List 1888, 23; (12) Oates ed. Hume Nests & Eggs 
Ind. B. 1890, IH, 299; (13) Salv., Orn. Pap. Agg. 1891, 211; (14) Kbnig, J. f. 0. 
Meyer & Wigleswortli, Birds of Celebes (Dee. 14 th, 1897). 1 13 
