Todd-Carriker : Birds of Santa Marta Region^ Colombia. 323 



data than in columbiana, the inner web of the outer rectrix often be- 

 ing wholly white in the former, while in the latter there is always at 

 least a subterminal spot of black. The black frontal area averages 

 broader, and the bill a trifle stouter, in semifasciata. Females afford 

 much better characters for separation, the upper surface being 

 browner (the pileum especially), less grayish in columbiana than in 

 semifasciata. It would appear that far too much importance has been 

 attached to the color-pattern of the tail in discriminating certain 

 members of this group, and this character must be used with caution. 

 Examination of the present fine series discloses the existence of a 

 great deal of variation in this respect. In some males there is merely 

 a spot of black (not touching the shaft) on the inner web of the outer 

 rectrix toward the tip, and often this spot is asymmetrically developed 

 on the two sides. From this condition there is- every gradation up to 

 birds showing a broad black subterminal band, equally developed on all 

 the rectrices. Such examples correspond in this respect to the de- 

 scription of T. semifasciata esmeraldce Chapman {Bulletin American 

 Museum of Natural History, XXXIII, 1914, 320), which, were it 

 dependent on this character alone, could scarcely be considered valid. 

 Precisely the same range of variation obtains in the Costa Rican form, 

 T. semifasciata costariccnsis, and the only observable difference be- 

 tween males of this latter form and of columbiana is the whiter under 

 surface of the latter, evident on comparison in series. Females of the 

 two forms, however, are very different, as indicated by Mr. Ridgway. 

 One bird sexed as a female (No. 38,114, Minca, August 19, 1911) has 

 the inner web of the two outer rectrices pure white, this being an ex- 

 treme case. Another specimen shot July 21 is in juvenal dress, with 

 short wings and tail. 



A fairly common bird over the western lowlands, as well as the foot- 

 hills and lower slopes of the north and east sides of the mountains. 

 It is essentially a Tropical Zone species, going up only to about 5,000 

 feet, and probably wanders about considerably except in the nesting 

 season, breeding in the lower altitudes. It is much addicted to perch- 

 ing on tall dead trees. 



273. Erator albitorques (Du Bus). 



Tityra albitorques Salvin and Godman, Ibis, 1880, 169 (Valencia). — Sclater, 

 Cat. Birds Brit. Mus., XIV, 1888, 332 (Valencia).— Allen, Bull. Am. Mus. 

 Nat. Hist., XIII, 1900, 155 (Salvin and Godman's reference). 



