22 BULLETIN 86, UNITED STATES NATIONAL MUSEUM. 



faimal papers or books on birds of large groups or extended geo- 

 graphic areas. The two most vahiable articles on the genus as a 

 whole are, of course, Dr. Hartert's account in the Catalogue of Birds 

 in the British Museum, and in the Tierreich. Full citation of these 

 and the other more important papers dealing wholly or in part 

 with the birds of the present genus are given in the following chrono- 

 logical list, from which, however, are omitted references to several 

 of the original descriptions, since these can be found in the synonymy 

 of the various forms of the genus : 



Spix, J. B. — ^Avium Species Novae, quas in itinera per Brasiliam annis 1817- 

 1820 colleg. et descripsit ; vol. 2, 1825, p. 2, pi. 2. 



Cassin, John. — Illustrations of the Birds of California, Texas, Oregon, 

 British and Russian America ; 1855, pp. 237-239. 



BuBMEiSTEE, C. H. C. — Systematische Uebersicht der Thiere Brasiliens, vol. 2, 

 1856, pp. 393-397. 



Baird, S. F. — Reports of Explorations and Surveys to Ascertain the most 

 Practicable and Economical Route for a Railroad from the Mississippi River to 

 the Pacific Ocean, vol. 9, 1858, pp. 150-1.55. 



ScLATER, p. L. — Notes upon the American Caprimulgidte. Subfamily III. 

 Caprimulginse. Proceedings of the Zoological Society of London, 1866, pp. 

 331-135. 



Pelzeln, August von. — Zur Ornithologie Brasiliens, 1 Abth., 1868, p. 14. 



Baird, S. F. ; Brewer, T. M. ; and Ridgway, R. — History of North American 

 Birds; Land Birds, vol. 2, 1874, pp. 399-408. 



Taczanowski, Ladislas. — Ornithologie du Perou, vol. 1, 1884, pp. 210-215. 



CouES, Elliott. — Key to North American Birds, second edition, 1884, pp. 453- 

 455. 



Shufeldt, R. W. — Contribution to the Comparative Osteology of the Tro- 

 chilidfe, Caprimulgidse, and Cypselidse. Proceedings of the Zoological Society 

 of London, 1885, pp. 886-915, pis. 5S-61. 



Ridgway, Robert. — Manual of North American Birds, 1887, pp. 297, 300-301. 



CotJES, Elliott. — New Forms of North American Chordiles. Auk, vol. 5, 

 January. 1888, p. 37. 



Hartert, Ernst. — Chordeiles. Catalogue of the Birds in the British Mu- 

 seum, vol. 16, 1892, pp. 521, 609-^18. 



Salvin, Osbeet ; and Godman, F. D. — Biologia Centrali-Americana ; Aves, vol. 

 2, November, 1894, pp. 395-398. 



Bendire, Charles. — Life Histories of North American Birds, from the Par- 

 rots to the Crackles, with Special Reference to their Breeding Habits and Eggs, 

 1895, pp. 163-174. 



Hartert, Ernst. — Das Tierreich. I. Lieferung: Podargidae, Caprimulgidae, 

 und Macropterygidae, 1897, pp. 18-21. 



Beddard, F. E.— The Structure and Classification of Birds, 1898, pp. 234-242. 



Coues, Elliott. — Key to North American Birds, fifth edition, vol. 2, 1903, pp. 

 563. 568-570. 



Hellmayr, C. E. — The Birds of the Rio Madeira. Novitates Zoologicae, vol. 

 1910, p. 378. 



Key to sp&cies and subspecies. — The following key to the forms of 

 Chordeiles is confessedly but little more than a comparative state- 

 ment of characters, although purposely rather full ; and while it may 

 in some cases suffice for the identification of a bird in hand, its main 



