Hirundo gutturalis Scopoli, Del. Flor. et Faun. Insubr. (1786),
2, 96; Sharpe, Cat. Birds Brit. Mus. (1885), 10, 134; Hand-List
(1901), 3, 193; Whitehead, Ibis (1899), 236; Oates and Reid,
Cat. Birds' Eggs (1903), 3, 238; McGregor and Worcester, Hand-List
(1906), 70.
Basilan (Bourns & Worcester); Bohol (McGregor); Cagayan Sulu
(McGregor); Calayan (McGregor); Cebu (McGregor); Cuyo (McGregor);
Fuga (McGregor); Guimaras (Steere Exp., Bourns & Worcester); Luzon
(Everett, Steere Exp., Bourns & Worcester, McGregor); Maestre
de Campo (McGregor & Worcester); Mindanao (Steere Exp., Bourns
& Worcester); Mindoro (Bourns & Worcester); Palawan (Bourns &
Worcester); Panay (Steere Exp., Bourns & Worcester); Semirara
(Worcester); Sibay (McGregor & Worcester); Siquijor (Bourns &
Worcester); Sulu (Bourns & Worcester); Ticao (McGregor). Malay
Peninsula and Archipelago, Indo-Chinese provinces; central and
eastern Siberia, China, Japan, New Guinea, Australia.
Adult (sexes similar).--Forehead, chin, and throat dark chestnut,
lores black; upper parts dark steel-blue; feathers of hind neck and
upper back with much white basally; sides of head and neck, and a
broad, more or less interrupted, band on breast steel-blue; rest of
under parts white, sometimes tinged with pale salmon-pink; wings and
tail black, glossed with green; each of the rectrices except middle
pair with a large white spot on inner web. Length, about 175; wing,
118; tail, 90; depth of fork, 47; bill from nostril, 6; tarsus, 10.
Young birds have the forehead, chin, and throat brown or whitish,
and the breast-band and sides of head earthy brown.
Typical specimens of the common and eastern swallows are no doubt
very distinct, but the two forms appear to intergrade so that some
authors have rejected the latter species, although it seems now
to be generally recognized. Sharpe says in part: "If one accepts
the broken pectoral collar as the best sign of distinction between
H. gutturalis and H. rustica, it will be found to be so only in the
majority of specimens, and by no means invariably; in fact there is
as much variation with H. gutturalis in the direction of a complete
collar on the fore neck as there is in H. rustica in that of a broken
collar. Again, although the majority of H. gutturalis have a white
under surface, still this is not an unfailing character of the eastern
race; for many undoubted examples are rufescent below, although there
is never such a decided tint of rufous as in full-plumaged H. rustica."