12 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I46 



Females (12 specimens), wing 444-459 (449.3), tail 193-230 

 (206.8), oilmen from cere 21.2-24.0 (22.1), tarsus 56.2-60.0 (58.0), 

 approximate width of central rectrix 43-49 (46.3 ) mm. 



Ratige. — Eastern Mexico, in Tamaulipas (Tampico; Lomas del 

 Real), A'eracniz (Veracruz; Alvarado), and Tabasco (Miramar; 

 \'illa Hermosa) ; British Honduras (Belize) ; Honduras (Puerto 

 Lampira) ; Pacific slope of Panama from Chiriqui (David) through 

 \'eraguas (Sonaj, Code (Rio Hato; Anton), Herrera (El Rincon ; 

 Pese; Santa Maria), and Los Santos (Pedasi) to eastern Province of 

 Panama (La Jagua; Rio Chico) ; Colombia from Atlantico, Magda- 

 lena (Santa Marta; Gaira), and Guajira (Maicao) south locally to 

 the upper Rio Cauca, upper Patia Valley in Cauca, the upper Magda- 

 lena \*aUey in Huila, and, in the northern llanos, to northern Meta 

 (Quenane) ; northwestern \>nezuela, in Zulia (Encontrados) and 

 Falcon (El Planchon). 



There is some seasonal variation in depth of color of the head. An 

 adult female near breeding stage shot on March 24, 1961, at La Jagua, 

 Panama, had the iris orange-red ; center of the croum indigo, in an 

 irregular triangle with the apex forw-ard and the base behind, 

 bordered narrowly on either side by pale greenish blue ; side of head, 

 including the loral area and the base of the mandibular rami, bright 

 orange ; the bare f oreneck, including the prominent caruncles, dull 

 orange : back of the head dull blue, crossed by three irregubr rows of 

 caruncles which are dull orange; bill dull ivory white; crus dull 

 yellowish white; front of tarsus dull greenish gray, rest dull white; 

 toes fuscous black ; claws fuscous. In another female, also adult but 

 in resting stage, taken at the Cienaga Macana, Herrera, March 17, 

 1948, the iris was red ; center of crown and spot in front of the eye 

 dull bluish gray; cere, forepart of crown to center of eyes, nape, 

 back of head, and neck to throat dull orange-red; lores greenish 

 yellow ; sides of head from posterior loral space back around the eye 

 and ear, including the area below the gape, bright orange. A com- 

 panion bird taken at the same time was slightly duller. 



In Mexico and Central America the yellow-headed vulture tends 

 to frequent lowland marshy areas that often are difficult of access. 

 As it is far less common than the red-headed turkey vulture, found 

 everjnvhere, it may be overlooked since the two are closely similar 

 except in the head color, which is seen only under favorable condi- 

 tions. Now that attention has been attracted there have been recent 

 reports that have added considerably to the details of range. Dr. and 

 Mrs. Richard R. Graber (1954, pp. 165-166) collected one on July 21, 



