82 Mr. O. Salvin and F. D. Godman on 



along the culmen of tlie uill than in L. verreauxi, and in this 

 respect recall this peculiarity in the genus Orthorhynchus. 



Ch^tura rutila. 



Two specimens of a Swift from the Merume Mountains, 

 though closely resembling Guatemalan examples of the bird 

 we have been in the practice of calling ChcBtura rutila, present 

 differences which are doubtless specific. 



The rufous collar which distinguishes these Swifts is of a 

 briobtcr colour in the Guiana bird, and extends quite over 

 the chin, the feathers of this part in the Colombian bird 

 being sooty black like the rest of the plumage. The tail of 

 the former is much longer and distinctly forked, that of the 

 latter being nearly square and the feathers more spinous. 

 We do not, however, attach much importance to this latter 

 character, as the difference may be due to the extent to 

 which the tail-feathers have been abraded by contact with 

 the rocks &c. which these birds frequent. 



There can be little doubt that the species described as 

 Hirundo rutila by Vieillot was the Guiana bird, though the 

 orifin of the specimens was unknown. To this bird the name 

 Hirundo robini also applies, judging from Lesson's descrip- 

 tion and also from that of Leotaud, the bird being an inha- 

 bitant of the island of Trinidad. Equally certain is it that 

 Lafresnaye's name Chaiura brunneitorques is applicable to 

 the Colombian form, which -we trace southwards to Ecuador 

 and northwards through Central America as far as Southern 

 Mexico. 



The references to these Swifts may be thus apportioned: — 



CHiETURA RUTILA. 



Hirundo rutila, Vieill. N. Diet. d'Hist. Nat. xiv. p. 528; id. 

 Ene. Meth. p. 584; Leotaud, Ois. Trinidad, p. 85. 



Chaiura rutila, Scl. P. Z. S. 1863, p. 100, et 1865, p. 613 

 (partim). 



Hirundo robini. Less. Traite d'Orn. p. 270. 



Hab. Guiana, Merume Mountains {Tlhitely) ; Trinidad 

 {Robin, Leotaud). 



