Phaethon Linn., Syst. Nat., 10th ed.; i, p. 134 (1758).
Type by orig. desig., Phaethon aetherius Linn.
In this genus the bill is short, stout, with the culmen curved throughout and the margins finely serrated : the wings are very long and pointed with the first primary longest; the middle rectrices are excessively elongated and attenuated, looking like streamers in flight; the tarsus is short and fairly stout.
Three species have been recorded as occurring within the limits of this work and the genus is represented throughout the tropical seas of the world.
These birds are known among sailors as the Bo'sun Birds.
Key to Species.
A. Elongated central rectrices white.
a.Back barred in adults; white tips to primaries very narrow; tail-feathers 14……………P. indicus, p. 291.
b. Back white in adults; white tips to first primary over 12 mm.; tail-feathers 12……………P. lepturus, p. 293.
B. Elongated central rectrices deep red……………P. rubricauda, p. 292.