PHAETIIONTID^ — THE TROPIC BIRDS — PHAETHON. 



185 



Family PHAETHONTID^. — The Tropic Birds. 



Char. Bill conical, much compressed, the maxillary tomium exceedingly con- 

 cave in the middle portion, descending, convex, and bulging outward at the base ; 

 culmen gently curved ; nostrils very distinct, linear ; head normally feathered. 

 Primaries much elongated in proportion to the secondaries ; tail very short, gradu- 

 ated, the central pair of rectrices linear and excessively elongated (longer than the 

 wing) in the adult. Lateral toes nearly equal (outer longest), and but little shorter 

 than the middle. Plumage very compact, satiny. Color chiefly white. 



This family is composed of the single genus Phaethon, of tropicopolitan range, 

 and represented in America by two of the three known species. 



Genus PHAETHON, Linnaeus. 



Lepturus, Briss. Orn. VI. 1760, p. 479. 



Phaethon, Linn. S. N. ed. 10, I. 1758, 134; ed. 12, I. 1766, 219 (type, P. cethereus, Linn.). — 



Lawr. in Baird's B. N. Am. 1858, 885. 

 " Tropicophihis, Leach," Steph. Gen. Zool. XIII. i. 1826, 124. 

 Phmnicurus, Bonap. Consp. II. 1857, 183 (tj'pe. Phaeton phoenicuros, Gmel.). 



P. flavirostris. 



Char. Same as those of the family. 



The three known species of this genus are very well marked, and may be easily distinguished 

 by the following characters : — 



A. Elongated middle rectrices, with their webs very much broader than the moderately rigid 

 shaft. 



1. P. flavirostris. Bill yellow ; middle tail-feathers pinkish, with black shafts ; wing about 



1 1 .00 inches ; culmen 2.00 or less. Hah. Intertropical seas, north to Florida. 



2. P. aethereus. Bill deep coral red ; middle tail-feathers pure white, with white shafts ; 



wing about 12.00 inches ; culmen about 2.50. Hah. Intertropical seas, north to Lower 

 California. 

 VOL. II. — 24 



