FREGATID^. 15 



a. Plumage of the head and iieck^ as well as most all of the upper parts^ 

 pure iL'hite. 



b. Greater part of tail feathers broivnish black; naked skin of the face and 

 throat blackish (blueish in life); neck and body entirely white; primaries, secondaries 

 together with most of the tail, brownish black; wing coverts white. Young: Head, neck 

 and upper parts plain dark brown ; part of the neck streaked with white. Nestlings 

 covered with white down-. Length 25.00-29.00, wing 15.00-17.00, tail 8.25-10.00, 

 culmen 3.60-4.25, depth of bill i. 40-1. 60, tarsus 2.25, middle toe 3.25. Hat. Central 

 Pacific Ocean. Laysan, French Frigates, Midway, etc. 

 PI. XXI., 7933. 22. S. cy'anops Sund. Blue-faced Booby. 



bb. Tail pure luhile; outer web of primary feathers hoary grey; outer webs 

 of secondaries and their coverts hoary ; smaller wing coverts white like the rest of the 

 body; all more or less rich white and tinged with buff; feet reddish. Young: Above 

 sooty brown, hind neck and lower parts light smoky grey (plumage extremely variable) . 

 Length 23.00-27.00, wing 15.00, tail 6.75-7.25, culmen 3.40-3.50, depth of bill 1.40. 

 Hab. Inter-tropical seas. Niihau, Oahu, Lisianski, Laysan, French Frigates, etc. 

 PL XXI., 7933. 33. S. pisca'tor (Linn.). Red-footed Booby. 



aa. Plumage of the upper parts uniform deep sooty brown; head, neck and chest 

 deep sooty brown like the back ; lower parts white ; tail and wings u.niform with the 

 back. Young: Nearly uniform sooty brown, paler beneath. Length 30.00-31.00, wing 

 15.50, tail 7.50, tarsus 1.80, culmen 4.00 (4.25 ? ). Hab. Tropical seas. Niihau, 

 Laysan, etc. 



PI. XXI., 8752. 34. S. sula Linn. Booby. 



Family FRBGATID^.— Man-o'-war Bird. 

 Genus. 

 Chara6lers for the genus same as for the family (Page 15.) Frega'ta. 



Genus FREGATA Cuvier. 



Culmen more than 4.25 ; bill long and strongly hooked at the extremit}^, both 

 mandibles being curved downward. Male: Breast and sides sooty black and culmen 

 strong; feathers of the head, back and scapulars elongated, pointed, and a glossy oil- 

 green with a bronze sheen (no white on the flanks); gular pouch scarlet orange 

 (fading). Female: Breast and sides white; culmen longer (5.00); head and neck not 

 so glossy ; back of the neck, lesser and median wing coverts brown with paler margins. 

 Young., both sexes: Head and neck as well as upper half of chest white with an occa- 

 sional rusty feather about head and sides ; upper breast dark sooty brown ; otherwise 

 as in the female. Length 37.50-41.00, wing 23.00-25.00, tail 15.00, tarsus .65. Hab. 

 Tropical and sub-tropical seas. Hawaiian Islands. 



25. F. a'quila Linn. Man-o'-war Bird, Iwa. 



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