520 BIRDS OF THE REPUBLIC OF PANAMA PART 2 



Measurements. — Males (10 from Panama) wing 125.8-142.7 

 (134.4), tail 114.4-128.8 (121.6), culmen from base 91.3-106.6 

 (97.9), tarsus 36.3-39.8 (37.8) mm. 



Females (10 from Panama and Choco, Colombia), wing 130.2-139.0 

 (134.6), tail 113.0-123.4 (120.3), culmen from base 83.5-90.0 (85.5), 

 tarsus 35.2-38.0 (36.6) mm. 



George V. N. Powell saw several on Cerro Campana during No- 

 vember 1966. McLeannan sent a specimen from the northern Canal 

 Zone to Lawrence. There is a female in the Museum of Vertebrate 

 Zoology collected northwest of Gatun, November 2, 1947 by R. Noyes. 

 They are regular in occurrence in the forests near Pina, west of the 

 mouth of the Rio Chagres, and in 1961 I found them on Rio Boqueron 

 above Madden Lake. Von Wedel secured several near Puerto Obaldia 

 in the eastern San Bias. 



In eastern Panama, I saw them rather regularly on the slopes of 

 Cerro Chucanti, in March 1950, and collected 1 from a little flock 

 near El Real on March 21, 1964. Barbour, in April 1922, secured 

 4 on Cerro Sapo, and members of the Fifth George Vanderbilt 

 Expedition collected others there in 1941. I have 1 specimen from 

 La Laguna on the lower slopes of Cerro Tacarcuna, taken by Pedro 

 Galindo, June 6, 1963. Goldman secured several on Cerro Pirre in 

 April and May 1912. 



The present species has its distribution in Panama through the 

 forests inhabited by the collared aracari, but is far less common. The 

 two species, similar in general form but not in color, may come to the 

 same fruit-bearing trees for food, but otherwise remain apart in 

 separate pairs or small groups. I have noted no aggressive behavior 

 between them, but nowhere have I found either in sufficient abundance 

 to occasion any active competition. Their only common ground that 

 might be competitive is in holes in trees for sleeping and nesting. Such 

 shelters, however, appear to be sufficient in number for these and 

 other species of similar habit. 



Cassin's aracari, in contrast to the other species remains mainly in 

 the leaf canopy of the taller trees, moving and flying through this 

 cover. Less often does it fly across broad open spaces. Its duller 

 color pattern on the whole, coupled with more retiring habits, afford 

 it a certain measure of protection, so that it may be missed in casual 

 travel through its range. 



The call, a slowly repeated kr it-it krit-it, suggests that of the keel- 

 billed toucan, but is lower, with less carrying power, is shorter, and 

 is not repeated as steadily. Usually, when seen they rest quietly, 



