TROPIC BIRD. 473 



John R. Beath of Philadelphia, informs me that he mounted a specimen of the Frigate 

 Bird which was taken at Capo May Court House, in the spring of 1877. It is difficult to 

 find words which will convey an idea of the magnificent flight of these fine birds, but a 

 glance at the sternum as described un'der Family heading, will give some impression of the 

 bony frame-work which is intended to support the birds in their untiring journey through 

 the air; and thus armed against the forces of nature, nothing can daunt them. I have seen 

 them, when the wind blew high, circling with motionless wings and calmly breasting the 

 rising gale. The storm bursts and the waves are lashed into fury by the raging hurricane; 

 great trees on the neighboring land, which have stood the blasts of a hundred years, totter 

 and fall; while the spray flies in clouds from the now mountainous breakers; even then, 

 when all else bows to the relentles Storm King, the noble Frigate Bird does not deign to 

 alight, but with a few strokes of his strong pinions, moves majestically into the very teeth 

 of the driving elements, or plunging downward, will sail as grandly above the tempestuous 

 billows, as the Swallow skims over the surface of the summer lake, showing that in the 

 Man-of-war Bird, the power of flight is developed in the highest degree. 



FAMILY VI. PIL^TO-NID^E. THE TROPIC BIRDS. 



Bill, about equal in length to head, strong, and pointed at tip. Gular sac, absent. 

 Sternum, longer than wide. Keel, projecting forward considerably. 



The oesophagus is wide and somewhat dilated. Proveutriculus, large with glands ar- 

 ranged in a zonular band. Stomach, small and not muscular; Coeca, very small. Ster- 

 num, arched, with the central posterior margin concave. Keel, high. Furcula, short and 

 lying nearly perpendicularly. Head, not crested. Legs and neck, very short. 



, CiENUS I. PILETON. TI1E LONG-TAILED TROPIC BIRDS. 



GEN. Cu. Resemble those given under Family heading. Tail, wedge-shaped, with central feathers excessively elon- 

 gated. Sexes, similar. There is but one s|>ecies within our limits. 



PH-3BTON FLAVIBOSTRIS. 

 Yellow-billed Tropic Bird. 



Pfufton Jlavirostris BDT., Bull, So. Acad. Imp. St. Pet. I; 1837, 349. 

 DESCRIPTION. 



Sr. Cu. Form, slender. Size, medium. COLOR. Adult. White throughout with a satiny gloss, tinged with pale 

 salmon which becomes deeper on elongated central tail feathers, the shafts of which are black. Curved patch on side of 

 Ix'inl, unc on scnpularies and secondaries, passing back war 1 in a line along wing coverts, and spot near terminal portion of 

 primaries, purplish-Mack. The feathers of flanks arc centrally streaked with dusky. Hill, tarsi and base of feet, orange, 

 remainder of latter, black, iris, brown. Young. Similar but paler, and the central tail feathers are nut as long. 



OBSERVATIONS. 



Known by the donated central tail feathers and orange bill. Constantly resident on ttie Bermuda and Bahama Is- 

 hni'is. Rare on the Florida coast. Accidental in the Northern Atlantic States. 



DIMENSIONS. 



Average measurements of specimens. Length, 30'75; stretch, 37'00; wing, 1T25; tail, 19'25; bill,2'10; tarsus, P08. 

 Longest specimen, 32'00; greatest extent of wing, :!8-<X); longest wing, ll'SO; tail, 21 '00; bill, 2'25; tarsus, T25. Shortest 

 specimen, 29-50; smallest extent of wing, SG'OO; shortest, wing, ll'OO; tail, 18'50; bill, 2'00; tarsus, -90. 



DESCRIPTION OF NKSTS AND KUG.S. 



Efl'jf, usually placed in holes of rocks, one in numlier, rather oval in form, chalky-white in color, usually very thickly 

 spotted with reddish-chocolate of varying .shades. Dimensions IVom l-OOx'J'I/) to I'60x2'25. 



HABITS. 



Some years ago, when sailing along the Gulf of Mexico, not far from the Florida Keys, 

 in little sleaiinT, early in November, I observed a Tropic, Bird flying high in air. Tin; 

 bird was pursuing the same course that we were and remained in sight lor several hour. 



en 



