450 PHAETHOKllD^. 



Family IV. PHAETHONTID.E. 



Nostrils pervious. Palatines completely separate one from 

 the other ; vomer present ; a deep nasal hinge ; carina extending 

 nearly the whole length of the corpus sterni ; free end of clavicle 

 not provided with a facet for articulation with the acrocoracoid. 

 ( W. P. Pycraft.) 



1. PHAETHON* ^yp^ 



Lepturus, Moehr. A v. Gen. p. 64 (1752) ; Bris. Oni. 



vi. p. 479 (1760) P- tethereus. 



Phaeton, Linn. S. N. i. p. 219 (1766) P. sethereus. 



Phaethon, Illiffer, Prodromus, p. 280 (1811) P. ajthereus. 



Tropicophilus, Leach, fide Stephens in Shmv's Gen. 



Zool. xiii. pt. i. p. 124 (1826) P. jetbereus. 



Pbcenieurus, £o7iap. Consp. Av. ii. p. 183 (1855) P. rubricauda. 



Bill compressed, pointed, and slightly curved throughout, the 

 cutting-edges of the mandibles serrated ; nostrils distinct, linear ; 

 wings long, first primary rather longer than the second ; tail 

 composed of from 12 to 16 feathers, the middle pair being greatly 

 elongate and attenuated ; tarsus very short. 



Eancfe. Intertropical seas. 



Keii to the Species. 



I. Outer primaries with the outer web white to 



the base ; elongate middle tail-feathers car- 

 mine with black shafts rubricauda, p. 451. 



II. Outer primaries with the greater part of the 



outer web black ; elongate middle tail-feathers 

 white or apricot-colour. 

 A. Bill mostly yellow ; back uniform, not trans- 

 versely barred with black ; scapulars with 

 the terminal half mostly black ; outer web 

 of first primary white at the tip for at least 

 half an inch. 

 a. Black on outer web of outer primaries 

 ceases an inch or more from the ex- 

 tremity ; the third primary nearly as 

 widely tipped with white as the first; 

 basal two-thirds of both mandibles more 

 or less blackish horn-colour. 

 a'. General colour of plumage pure white . lepturus, p. 453. 



* The following works refer to the osteology and anatomy, etc., of the 

 genus : — Brandt, Mem. Acad. St. Petersb. (6) v. pt. ii. Livr. ii. pp. 122, 150, 

 190, pi. X. (1839), Livr. v. pp. 240-252, 274, pi. v. (1840) [anatomv, etc.] ; 

 Nitzsch, Pteryl., Engl. ed. p. 161 (1867) ; Eyton, Osteol. Av. p. 219 (1867). 



