FAMILY ARDEIDAE 95 



in the lowlands of Darien near La Palma and El Real. In 1965 it was 

 present in equal number near El Volcan in western Chiriqui. I have 

 identified the head of an immature individual, only recently from the 

 nest, collected in October 1961 at Almirante, Bocas del Toro, for Dr. 

 Conrad Yunkers of the Middle America Research Unit, An adult 

 taken at the same time had the buff of the breeding season on the 

 crown. It is probable that this species, in common with its habit else- 

 where, will join nesting colonies of other herons. 



These birds often perch on the heads or backs of the cattle among 

 which they feed. The yellow bill marks them instantly from the other 

 herons of similar size. 



Some ornithologists have placed the cattle egret under the genus 

 Ardeola Boie, type Ardea ralloides Scopoli, to which superficially it 

 appears similar. It is found however that the dorsal plumes of the 

 species ibis in the adult are hairlike and that the immature is plain 

 white. In Ardeola the dorsal plumes have barbs extending nearly to 

 the tips, and the neck and upper breast in the immature are heavily 

 streaked. Differences in the skeleton are of greater importance; e.g., 

 the entire leg in Ardeola is much shorter, but the femur and the fibula 

 equal those of the longer-legged Bubulcus. The spina externa is very 

 much heavier, though the entire sternum is shorter. Though the 

 humerus in Ardeola is definitely shorter, the brachialis anticus depres- 

 sion is larger, and the crista superior reduced. In the skull the anterior 

 part of the palatines is broader. These are part of the differences 

 which in sum maintain the two in separate genera. 



AGAMIA AGAMI (Gmelin): Agamf Heron; Garza Pechicastana 

 FlGUSE 15 

 Ardea Agami Gmelin, Syst. Nat., vol. 1, pt. 2, 1789, p. 629. (Cayenne.) 



In any plumage known by the elongated, narrow bill, 125 to more 

 than 160 mm. in length. 



Description. — Length 660 to 760 mm. Adult, dark glossy green 

 above; deep chestnut-brown below, including sides of neck; sides of 

 head and hindneck black ; lower f oreneck, and pointed nuchal crest, 

 light bluish gray. In breeding season the ribbonlike feathers of the 

 crest reach a length of 125 mm., and broad ornamental plumes grow 

 from the lower back. 



Immature, deep brown above ; blackish on crown and back ; streaked 

 buff, white, and black below. 



Iris light reddish brown ; eyelids, and a narrow border around base 

 of mandible, yellow ; loral area, and bare space around eye, yellowish 



