1917.] Chapman, Distribution of Bird-life in Colombia. 637 



(4547) Cyanocorax violaceus Du Bus. 



Cyanocorax violaceus Du Bus, Bull. Acad. Brux., XIV, pt. 2, 1847, p. 103 

 (Peru). 



Found only in the Tropical Zone at the eastern base of the Eastern Andes. 

 Our specimens are from La Morelia and Villavicencio where we found it as 

 high as 3500 ft. Young just from the nest were taken near Villavicencio 

 March 15. I have no Peruvian specimens for comparison. 



La Morelia, 5; Villavicencio, 6; Barrigon, 3. 



(4549a) Xanthoura yncas galeatus (Ridgw.). 



Xanthoura yncas galeata Ridgw., Auk, XVII, 1900, p. 27 (western Colombia; 

 I suggest El Eden, Cen. Andes). 



Cyanocorax incas Wtatt, Ibis, 1871, p. 330 (4000 ft. upward, Bucaramanga 

 region); Scl. & Salv., P. Z. S., 1879, p. 510 (Retiro; Concordia; Sta. Elena). 



There are two well-marked forms of Xanthoura in the Subtropical Zone 

 of the Bogota region; the present, and X. y. cyanodorsalis DuBois. X. y. 

 galeatus is here restricted to the western slopes of the Eastern Andes, and is 

 found also on both slopes of the Central Andes and in the more southern 

 parts of the Western Andes; X. y. cyanodorsalis is found on the eastern 

 slopes of the Eastern Andes and ranges northeastward at least to Merida, 

 Venezuela. Our series of over fifty specimens indicates clearly the range of 

 variation and characters of each of these forms. 



X. y. galeatus, as has been pointed out by Ridgway {I. c.) differs from 

 true yncas (of which we have three Peruvian specimens) in size and, mainly, 

 in the greater development of the nasal plumes; from cyanodorsalis it differs 

 strikingly and constantly (in fresh plumaged adults) in having the head, 

 posterior to the blue frontal plumes, and nape marguerite-yellow, .varying 

 in intensity. In some specimens it is clear, but more frequently it is tinged 

 with blue, especially at the junction with the back, which is green with, in 

 some specimens, a bluish wash. The amount of blue on the hindhead, 

 nape, and back is apparently largely dependent on age, young birds (with 

 small nasal plumes) having the maximum amount, sufficient in juvenal 

 plumage nearly to obscure the pale yellow of the head. 



In cyanodorsalis, the area which in galeatus is marguerite-yellow, is paler 

 and is restricted to the occiput the whole nape being blue; while the back 

 is usually well tinged with this color. 



The two forms are indeed strikingly different and there has not, I believe, 

 been any question as to their distinctness, but authors do not agree as to 



