PHAETHOXTIDjE: TROPIC BIRDS. 971 



PREGA'TA. (Ital. fregata, Span, and Port, fragata, in some other languages fregat, fregatt, 

 fregatte, Freuch fregate, a frigate; a word supposed to be formed from hut. fabricata, fabri- 

 cated, constructed, built.) Frigate Birds. Man-o'-war Birds. Hurricane Birds. 

 Rabihorcados. Characters as above given for the family. The following is the leading 

 species; a subspecies of this is F. a. miyior ; a probable second species is F. ariel. (Tachi/- 

 petes of most authors, as of all former editions of the Key.) 



F. a'quila. (In form Lat. aquila, an eagle, prob. =adj. aquilus, dark, swarthy.) Frigate. 

 Palmerston Frigate. Man-o'-war Bird. Hurricane Bird. Rabihorcado. Adult (^: 

 Brownish-black, glossed with green bronze or purple on head, scapulars and interscapulars, 

 where the feathers are long and lanceolate, duller on belly; wings usually showing some 

 brown or gray from wear. Adult 9= Less glossy than (J; less elongate feathers of head and 

 scapulars. Back of neck brown ; wing-coverts mostly brown, with darker centres and paler 

 edges ; fore neck, breast, and sides pure white. In <^ 9 > iris brown ; bill running through 

 various whitish or flesh-tints to livid bluish and blackish in old (J; bare space about eye livid ; 

 sac scarlet to orange; mouth carmine inside. Young: Most like adult 9 • niore extensively 

 white on head, neck, and under parts ; eyes, bill, feet, and soft parts livid bluish, or unde- 

 finable dark color. Length about 40.00, variable with development of tail ; extent 84.00- 

 96.00; wing 23.00-27.00; tail 15.00-19.00, forked more than half its length ; culmen 5.00-6.00 ; 

 tarsus 1.00 or less! Tropical and subtropical seas; in North America, South Atlantic 

 and Gulf coasts, regularly; N. casually to Nova Scotia, and in the interior to Ohio, Indiana, 

 Wisconsin, and Kansas ; on Pacific coast N. to Humboldt Bay, California ; accidental in 

 Germany in 17!>2 (Beciistein). Nests on trees and bushes, chiefly mangroves, or on rocks; 

 eggs 1-3, usually 1, 2.70-2.90 X 1.80-2.00, white, unmarked. 



Family PHAETHONTID^: : Tropic Birds. 



Bill about as long as head, stout, straight, compressed, tapering, acute, paragnathous, 

 with continuous horny sheath (lacking the sutures seen in other birds of this order). Head 

 rather large ; neck short and thick, with comparatively few vertebrae, which lack those pecul- 

 iarities of the articulating surfaces so marked in the kinky necks of Darters and Cormorants. 

 Gular sac rudimentary, almost completely feathered. Nostrils small, linear, but remaining 

 patulous. Tomia somewhat serrate. Tail of 12-14-16 feathers with the 2 middle ones in 

 adult filamentous and extraordinarily prolonged, the rest short and broad. Wings moderately 

 long, pointed. Feet small; toes fully webbed; hind toe more elevated than in other families 

 of this order; middle claw not pectinated. Among anatomical characters it is to be noted that 

 the muscles of the leg are as in Larida;, as might be expected from the outward resemblance 

 of these birds to Terns ; they having the accessory semitendinosus, lacking in other families 

 of the order. The biceps cruris does not pass through a loop. The skull is holorhinal, as it 

 is not in Gulls and Terns; the sternum is doubly notched behind. There is considerable 

 pneumaticity of the subcutaneous tissue, as in various other birds of the present i>rder. Tlie 

 plumage is close and smootli. The single egg is marked, contrary to the rule in this order ; 

 the nesting place is indiflFereutly on the ground, rocks, trees, or bushes. The young is covereil 

 with wliite fluff. 



Tlie Tropic Bird respuihks a large stout Tern in general figure; the bill, especially, being 

 almost exactly liUe tiiat of a Torn, and the system of coloration being similar. The principal 

 external peculiarity is the development of the middle tail-feathers ; the feathering of the gular 

 sac and the permanent patulanco of the nostrils are other features. They are strong and swift 

 birds on the wing, fly with quick regular strokes, and are capable of protracted flight, ventur- 

 ing far from land. They are gregarious at all times, and nest in communities along coasts and 



