THE BIRDS OF AUSTRALIA. 
Frigate Bird except that my unique $ has the largest beak of any 
recorded Frigate Bird ; my three males do not differ at all from birds 
killed by Dr. Ernst Hartert in the West Indies. This bird, which appears 
to occur on both sides of the American continent south of Florida, is 
quite a distinct species ; the ^ has entirely black wing-coverts and the ? a 
black throat and fore-neck. 
Mr. Mathews has made two subspecies of F. ariel Gould to occur in 
Australia ; as he founds his F, ariel tunnyi on size alone, and it resolves 
itseK into about 2 mm. difference in the bill and 15 mm. in the wing, this 
form is untenable. 
Below I give a key to the species and subspecies of Fregata^ of which 
the following is a list : 
F. aquila Linn., Ascension Island. 
F. andrewsi Math., Christmas Island. 
F. magnificens Math., Coasts and Islands of America. 
F. minor minor Gmelin, Eastern Indian Ocean. 
F. minor aldabrensis Math., Western Indian Ocean. 
F. minor palmerstoni Gmelin, Laysan, Fanning and other West Pacific 
Island groups. 
F. minor ridgwayi Math., Galapagos Islands. 
F. minor nicolli Math., South Trinidad. 
F. ariel ariel Gould, Australia. 
F. ariel iredalei Math., Western Indian Ocean. 
Males. 
, f Large white patch on sides of abdomen 9 
\ No white patch on sides of abdomen 2 
o f Back metallic green F. aquila. 
\ Back metallic purple F. magnificens. 
. { Abdomen and vent black 5 
I Abdomen and vent white F. andrewsi. 
« f Wing-band very broad and pale, breast greyish-brown F. minor nicolli. 
” I Wing-band narrower and darker brown, breast dark umber-brown F. minor 'palmerstoni. 
„ f Wing-band pale greyish-brown F. minor ridgwayi. 
^ I Wing-band very dark brown 8 
/Smaller, wing 530-550 mm F. minor minor. 
^ I Larger, wing 580-600 mm F. minor aldabrensis. 
/ Bill larger, 80 mm F. ariel arid. 
^ I Bill smaller, 68-70 mm F. ariel iredalei. 
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