262 BIRDS OF THE REPUBLIC OF PANAMA PART 3 



northward with the formation of the Panamanian land bridge. Under 

 present understanding it includes 7Z species, of which 20 are resident 

 in Panama. To the northward cotingas diminish in number, until 

 six are known in Mexico, with one, the Rose-throated Becard, found 

 rarely northward near the Mexican boundary in southeastern Ari- 

 zona, and in the lower Rio Grande Valley in southern Texas. 



Most members of the family superficially more or less suggest 

 tyrant flycatchers (family Tyrannidae) in appearance and habits. 

 Some, however, like the fruit-crows, vary in communal habit, as they 

 live regularly in small groups or bands. Others, the bellbirds and 

 umbrellabirds. are highly specialized in modification of head orna- 

 mentation, and in voice. The bellbirds locally are common and widely 

 distributed in forested areas, but are so secretive that their presence is 

 known mainly from their ringing, metallic calls. The even stranger 

 umbrellabirds are rarer and more retiring, so that in spite of large 

 size they are seldom seen, and little information on them and their 

 manner of life is available. 



Several of the smaller species of the family are widespread and are 

 common. Some come regularly with other berry-eating birds to feed- 

 ing trees. Several build large domed nests that may be readily visible, 

 but often are protected through location on branches near colonies 

 of stinging wasps, or of biting and stinging ants. 



The classification of several kinds in this family has not been 

 wholly certain. In the present account for those of Panama recent 

 studies of the anatomy of the syrinx has brought the transfer of 

 four generic groups long considered cotingas to the tyrant flycatcher 

 family (Tyrannidae). 



In earlier years the group was known as the chatterers. More 

 recently in both Spanish and English they are called cotingas, a name 

 for them in an Indian language of South America. 



KEY TO SPECIES OF COTINGIDAE 



1. Larger, wing more than 200 mm; head with a conspicuous crest; an ex- 



tensive area bare of feathers on the sides of the neck, or, in adult males, 

 the entire foreneck bare. 



Bare-necked umbrellabird, Ccphaloptcrus glabricollis, p. 306 



Smaller, wing less than 175 mm; head not prominently crested; neck 



normally feathered 2 



2. Mouth deeply cleft, the angle of the rictus extended back beneath the eye ; 



males with three long, pendant head wattles ; females with a rudimentary 

 wattle back of the rictus on either side ; chin extensively bare. 



Three-wattled bellbird, Procnias tricarnnculata, p. 302 

 Mouth normal; head without wattles; chin not extensively bare 3 



