1906.] NATURAL SCIENCES OF PHILADELPHIA. 179 



the birds obtained by Mr. Charles H. Townsend during the Pacific 

 cruise of the United States Fish Commission steamer "Albatross," in 

 1899-1900, and by specimens from the Academy of Natural Sciences 

 of Philadelphia, the American Museum of Natm-al History, and the 

 Bernice Pauahi Bishop Museum at Honolulu. To the authorities of 

 these institutions, to Mr. Townsend, Dr. Charles W. Richmond, and 

 Mr. Witmer Stone the -\\Titer's thanks are due for the courtesies which 

 have made this paper possible. 



Genus COLLOCALIA Gray. 



CoUocalia Gray, List Gen. Birds, 1840, p. 8 (type, Hirundo esculenta Linnaeus). 

 Salangana Lesson, Rev. Zool., 1840, p. 145 (type, Hirundo esculenta Linnaeus). 



Chars, gen. — Small and mostly rather plainly colored Swifts; outer 

 and middle toes with normal number of phalanges; tarsus not at all 

 or but sparsely feathered, and not shorter than the middle toe; wings 

 long, reaching when closed far beyond end of the tail ; tail short, nearly 

 square to somewhat deeply emarginate, the shafts of the rectrices 

 without spiny tips. 



Type. — Hirundo esculenta Linnaeus. 



Geographical range. — India and Ceylon, south to the Seychelles 

 Islands, east through the Malay Peninsula, the East India Islands, 

 and Polynesia, to the Philippine, Mariana, ^larquesas, Society and 

 Tonga groups, and northern Australia, 



Key to the Species and Subspecies of Collocalia. 



A. — Tarsus more or less feathered (subgenus Aerodramus). 



a. — Rump with a conspicuous white or brownish white band. 



h. — Centre of abdomen brownish gray like the breast; wing 



more than 120 mm., .... Collocalia innominata. 



b^. — Centre of abdomen white or nearly so; wing less than 120 



mm. 



c. — Upper parts brownish black; throat and breast nearly 



pure white like the abdomen; posterior lower surface 



without conspicuous dark shaft lines, 



Collocalia agnota. 

 c\ — Upper parts dull black, scarcely brownish; throat and 

 breast brownish gray like chin, and much darker than 

 abdomen; posterior lower surface with conspicuous 

 dark shaft lines, .... Collocalia leucopygia. 

 a^. — Rump without a conspicuous white or brownish white band. 

 h. — Feathers of lores with brownish bases, . Collocalia ocista. 

 ¥. — Feathers of lores with pure white bases. 

 c. — Wing not less than 124 mm. 



d. — Larger; upper surface lighter; lower surface with 

 conspicuous blackish shaft lines, Collocalia lowi. 



