230 BIRDS OF THE REPUBLIC OF PANAMA PART 3 



slate, lined narrowly with pale cinnamon-brown ; throat white or 

 buff ; rest of central lower surface white or with a wash of buff, the 

 breast spotted irregularly with olive or dull gray ; sides and flanks 

 olive to olive-buff ; tail as in male. 



Juvenile male, like female, but without concealed white on the back. 



These small birds are found in the undergrowth in gallery forest, 

 usually in pairs or small groups that may include a dozen individuals 

 when assembled over moving ant swarms. Attention is drawn to 

 them by their chattering calls, often scolding in sound, and their 

 trilling songs. They range low, immediately above the ants, often 

 fluttering excitedly from perch to perch. At rest, the tail is twitched 

 nervously and the slightly extended wings tremble. At times I have 

 found them near moving lines of leaf -cutting ants, though it seemed 

 that this was a casual association as the birds were less active and 

 made little noise. Because of their activities country men in eastern 

 Panama, especially in Darien, call them corregidor, the title of the 

 head official in small settlements, as they say that the bird by its calls 

 and active movements assembles and directs the activities of the 

 other avian species encountered with them. Like their companions 

 their food is taken from the insects and other small creatures dis- 

 turbed as the ants surge across the ground cover of leaves and 

 other debris. 



When away from the ant swarms, these ant-birds are found in 

 pairs that move through the undergrowth, near the ground. In 

 heavily shaded areas often they remain hidden as they are quiet with- 

 out the nervous display and active movements that they affect when 

 excited by the moving hordes of ants. Only the white collar on the 

 foreneck, that shows clearly even in subdued light, may attract the 

 human eye. (On life history, see Willis, A. O. U. Mon. 10, 1972.) 



In preparing specimens it will be noted that the head is especially 

 large in proportion to the size of the body so that the skull is passed 

 through the cylinder of the neck skin only with considerable pressure. 



As a species these birds range from the Caribbean lowlands of 

 eastern Honduras through Nicaragua and Costa Rica (where in 

 Guanacaste they cross to the Pacific slope). They continue on the 

 Caribbean side through western Panama in Bocas del Toro and 

 northern Veraguas, appear on the Pacific drainage on Cerro Campana, 

 and then are found where there is suitable forest cover on both slopes 

 through the Canal Zone and the whole of the lowlands of eastern 

 Panama in Darien and the Comarca de San Bias. They have not been 

 recorded on the Azuero Peninsula. 



