486 cypsELiDjE. 



the chin and throat ; the under tail-coverts, but not the abdomen, 

 bluish slaty black. Wing 4-3 inches. 



Ill the allied C. sclatcri the abdomen and rump are mnch darker, 

 and the metallic gloss on the upper parts is of a deeper, sometimes 

 rather purplish blue. 



Ucib. Eastern parts of Brazil. 



Snbsp. a. Chaetura guianensis. 



Acanthylis oxyura, LM. Ois. Trinidad, p. 84 (1866). 



Cliretura cinereiventris, Salv. Ibis, 1885, p. 4-37 (B. Guiana) ; Wells, 



Froc. U. S. Nat. Mus. ix. p. 020 (1886)'(Grenada) ; Cory, Aid; v. 



p. 158 (1888) ; id. B. W. hid. p. 294 (1889). 



This is merely a northern form of C. cinereiventris, and can be 

 recognized by the somewhat darker, more bluish colour of the 

 abdomen, and darker rump and upper tail-coverts. The wing seems 

 to be generally shorter, the specimens before me having the wing 

 4 to 4-2 inches in length. 



Besides the specimens in the British Museum, I had the oppor- 

 tunity of comparing some specimens sent me by my friend H. von 

 Berlepsch. 



Bab. Guiana, Venezuela, Trinidad (Mus. II. v. Berlepsch), and 

 Grenada. 



a. Ad. sk. Venezuela ? Salvin-Godman Coll. 



b, e. Ad. sk. Guiana ? Purchased 



d. 5 ad. sk. IJ. Atapurow, Brit. Guiana, Salvin-Godman Coll. 



Jan. 25 (//. WMtely). 



e. S fid. sk. Boraiuia, Brit. Guiana, April 11 Salvin-Godman Coll. 



(//. Whitehj). 



f. 2ad.sk. Meriune Mts., Brit. Guiana, July Salvin-Godman Coll. 



13 [H. Whitelii). 



18. Chaetura acuta. 



Ilirondelle noire acutipenne de la Martinique, Bvff. Hist. Nat. Ois, 

 vi. p. 702 (1779). 



Hirundo acuta, G7h. Syst. Nat. ii. p. 1023 (1788) ; Sfepit. Gen. Zool. 

 X. p. 131 (1817). 



Chsetura poliura, Laim: Proc. JJ. S. Nat. Mus. i. p. 62 (1878). 



Chaetura dominicana, Later. Ann. N. Y. Acad. Sc. i. p. 255 (1878) ; 

 id. Pr. U. S. Nat. Mus. i. p. 487 (1878) ; Lister, Ibis, 1880, p. 42 

 (St. Vincent) ; Scl. Ibis, 1880, p. 75 (Sta. Lucia) ; Coi-y, Auk, iii. 

 p. 346 (1886) ; id. £. W. hid. p. 141 (1889). 



Cbastura domiiiicaua colardeaui, Later. Auk, 1891, p. 59 (Guade- 

 loupe) (type examined). 



Adult. Deep blackish brown above with a very faint gloss ; rump 



