16 BULLETIN 98, UNITED STATES NATIONAL MUSEUM. 



STERNA MELANAUCHEN MELANAUCHEN Temminck. 



Sterna melanauchen Temminck, Nouv. Rec. Planch. Col. d'Oiseaux, vol. 5, livr. 

 72, 1827, pi. 427 (coast of Celebes). 



One specimen, No. 171030, U.S.N.M., Pulo Kelong, August 30, 

 1899. A few of the wing-quills are in molt. 



This example is identical with others from the Philippine Islands, 

 Amoy (China), and Condore Island, and represents the typical form 

 of the species, which was descrihed from Celebes. 1 Birds collected by 

 Doctor Abbott on the islands off the eastern coast of Africa, however, 

 are easily separable subspecifically, and as they hitherto have escaped 

 being named, all the synonyms of the species having been applied to 

 the typical race, they may be known as 



STERNA MELANAUCHEN PROVIDA, new subspecies. 



Subspecijic characters. — Similar to Sterna melanauchen melanau- 

 chen, but upper parts lighter, the mantle of a paler gray; bill longer; 

 wing, tail, and tarsus shorter. 



Description.— Type, adult male, No. 128756, U.S.N.M.; Provi- 

 dence Bank, 300 miles southwest of the Seychelles, north ol Mada- 

 gascar; August 17, 1892; Dr. W. L.Abbott. Crown, hind neck, upper 

 tail-coverts, tail, sides of head and neck, with entire lower parts, 

 including under side of wings, pure white; a spot on lores, and a 

 broad postocular band, broadening posteriorly and uniting with its 

 fellow across the occiput, black; back, rump, scapulars, and exposed 

 surface of wings, very pale pearl gray, this color showing faintly as a 

 narrow stripe along the shafts on the inner webs of the outer few 

 primaries, increasing on the rest of the wing-quills, which are tipped 

 and margined broadly on inner webs with white ; outer web of first 

 (outermost) primary all but tip and extreme base blackish slate; 

 bill and feet black. 



All the four specimens available present little individual variation 

 in either color or size, except, as is, for obvious reasons, often the case 

 with terns, in the length of the tail-feathers. There seems to be in 

 this species no size difference of consequence between males and 

 females. 



The geographic range of Sterna melanauchen provida comprises the 

 islands of Aldabra and Providence, with doubtless the neighboring 

 islands off the east African coast, north at least to the Seychelles. 

 The range of the typical form, Sterna melanauchen melanauchen, 

 extends probably from the Andaman Islands and Sumatra to the 

 Liu Kiu Islands, Polynesia, and Australia. 



The subjoined measurement tables will serve to show the size 

 differences between the two races here defined. 



i Temminck, Nouv. Rec. Planch. Col. d'Oiseaux, vol. 5, livr. 72, 1827, pi. 427. 



