NOVITATES ZoOLOaiCiE XXII. 191j. 145 



ON THE GENUS FREGATA. 



By THE Hon. WALTER ROTHSCHILD, F.R.S., Ph.D. 



IN the Austral Acian Record, vol. ii. No. 6, Mr. Mathews gives a synopsis of 

 the genns Fregata. 



There are several points in this synopsis which need revision. As Mr. 

 Mathews has stated, in the catalogue of birds only two species of the genus 

 are recognised under the names of F. aqiiila and F. ariel. It is therefore of 

 great importance to science that Blr. Blathews, by his careful study of the group, 

 was enabled to show that there are a number of other species and several sub- 

 species that have been overlooked. I regret much, however, that Mr. Mathews 

 has fallen into a fundamental error in regard to the species which must bear 

 the name minor Gmel. As he quite correctly states, the type of this name is 

 the bird figured on plate 309 of Edwards' Gleanings ; but he has failed to assign 

 this plate correctly, for by only taking note of the fact that Edwards' bird was 

 of unknown origin, he arbitrarily fixed the type locality as Jamaica. If he had 

 studied the plate and read the description carefully he could not have failed 

 to see that in Edwards' bird the throat and foreneck are white, while in all the 

 West Indian birds it is blackish. There is considerable internal evidence in the 

 text, besides the fact of the white throat, which proves the bird received by 

 Edwards to have come from the eastern half of the Indian Ocean, so I must 

 fix as the typical Fregata minor of Gmelin the birds of that area. 



A second error of Mr. Mathews is his placing the larger species found on 

 the Galapagos Islands as a subspecies of F. minor under the name of F. minor 

 " magnijicens." This bird does not differ from the West Indian Frigate Bird except 

 that luy 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 con- 

 tinent south of Florida, is quite a distinct species ; the S has entirely black wing- 

 coverts and the ? a black throat and foreneck. 



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 itself into about 

 'I 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. aqiiila Linn., Ascension Island. 



F. undrewsi Math., Christmas Island. 



F. ma.gniflcens 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 ridgwaiji Math., Galapagos Islands. 

 F. minor nicolli Math., South Trinidad. 

 F. ariel ariel Gould, Australia. 

 F. ariel iredalei Math., Western Indian Ocean. 

 ID 



