80 BULLETIN 17 9, UNITED STATES NATIONAL MUSEUM 



eaten whole. Sometimes, however, the flycatcher clung to the spadix 

 of the palm and gobbled down a few berries while hanging there. 

 The berries are about the size of large peas, with a thin yellow pulp 

 enclosing the single large seed." 



Behavior. — He says further (MS) : "Feeding with the fork-tailed 

 flycatchers were numerous Lichtenstein's kingbirds, whose persistent 

 twitters were in contrast to the silence of the former. Unimportant 

 clashes between the two species were frequent, and the kingbird 

 was usually the aggressor." 



Referring to his observations in Costa Rica, where he saw them 

 feeding on the ground, he writes (MS.) : "It seems strange that these 

 birds, which appear so aerial with their long, slender, streaming tail 

 feathers, should hug the ground so closely; by day I saw them only 

 resting low in the open places, or flying over them at no great eleva- 

 tion, never in the bushy lands of the valley, where most of the birds 

 of the neighborhood were to be found, nor perching in trees. They 

 are 'ground-grazers' like some of the Argentine flycatchers described 

 by Hudson. As they rested low among the grasslands, their white 

 breasts, when turned toward me, seemed in the distance to be the 

 great snow-white blossoms of some humble prairie herb. 



"Each evening, as the sun began to sink low above the forested 

 crests of the hills beyond the Rio Grande de Terraba, all the fork- 

 tailed flycatchers in the vicinity began to stream in toward the village. 

 With their long tails flowing behind them, they are no less graceful in 

 flight than their relatives the scissor-tailed flycatchers ; but since they 

 lack the scarlet and pink sides of the latter, they are far less color- 

 ful. Just as the scissor-tail slept in the orange trees behind the 

 jefatura of Las Canas in Guanacaste, so the forktails roosted in the 

 orange trees behind the casa cural (priest's house) in Buenos Aires. 

 Since the padre spends here only a few days during the course of the 

 year, the house had long been unoccupied when I arrived to lodge 

 there, and the birds had been unmolested. I found it impossible to 

 estimate how many of them gathered nightly in the orange trees; 

 there were scores of them, possibly hundreds. If I appeared at the 

 edge of the porch, or on the ground beneath them, while they were 

 arranging themselves for the night, many would dart rapidly forth 

 in all directions, with their long tails whistling as they rushed 

 through the air. Then, when I had vanished into the house, the birds 

 would return to their orange trees. Once darkness had descended 

 and they had fallen asleep, I could move quietly beneath them with- 

 out disturbing their slumbers. 



"In the morning they would linger in their roosting places after 

 awakening. If I appeared beneath them before they had quit their 

 sleeping places, many would rush forth with a great whistling of 



