(EYEBROWED TERN.)
+Sterna superciliaris+, _Scl. et Salv. Nomencl._ p. 147; _iid. P. Z.
S._ 1871, p. 571; _Durnford, Ibis_, 1877, p. 201 (Buenos Ayres);
_White, P. Z. S._ 1882, p. 628 (Misiones); _Saunders, P. Z. S._
1876, p. 662. +Sterna argentea+, _Burm. La-Plata Reise_, ii. p.
519 (Paraná).
_Description._--Forehead and underparts white; loral stripe, head,
and nape black; back, rump, inner primaries, and inner web of tail
pale slate-grey; outer primaries blackish; bill yellow; legs and
feet olive-yellow: whole length 8·5 inches, wing 7·0. In the young
bird the crown is grey.
_Hab._ The large rivers and the coast on the east side of South America.
This is a little Tern, belonging to the same group as the European
_Sterna minuta_, with a uniform pale yellow bill. Durnford met with
it at Baradero, and says that it frequents shallow inland lagoons and
small streams, but is also found on the Rio de la Plata. Dr. Burmeister
obtained it on the Paraná, and White at Itapua, Misiones. Saunders shot
it on the Huallaga, in Peru, 2800 miles inland.