1 66 BIRDS OF THE REPUBLIC OF PANAMA PART 4 



nation of egg-white proteins, concludes that they are more closely re- 

 lated to the silky-flycatchers and should be placed in that family, in a 

 position next to the Turdidae. The silky-flycatchers, sometimes given 

 sub familial rank in the Bombycillidae, were found by Sibley to be less 

 similar to the waxwings than to the solitaires. Ames (Bonn. Zool. 

 Beitr., vol. 26, 1975, pp. 125-127), in an examination of syringeal 

 morphology in the Muscicapidae, concludes that the generalized oscine 

 syrinx in Myadestes places it outside the Turdidae, but not necessarily 

 in the Ptilogonatidae. 



The 2 solitaires and 2 silky-flycatchers found in Panama are all high- 

 land birds living in forest and forest edges where they feed on fruit 

 and insects. All but the Varied Solitaire are restricted to Costa Rica 

 and western Panama; this last has an equally narrow distribution in 

 the highlands of eastern Panama and extreme northwestern Colombia. 



The solitaires are shy and their drab plumage makes them difficult 

 to see in the thick foliage, but their song makes up for their inconspicu- 

 ousness. The Black- faced Solitaire's loud, liquid, seemingly studied 

 whistles are among the most beautiful of bird songs. The song of the 

 Varied Solitaire, from what little is known, is harsher. Although es- 

 sentially arboreal except when they follow foraging bands of ants, 

 solitaires build their cup-shaped nest on or close to the ground. 



The silky-flycatchers, in contrast, are strikingly colored in patterns 

 of yellow and gray or black. The tapered, elongated tail of Ptilogonys 

 caudatus, black with white spots, is flashed dramatically in aerial acro- 

 batics when the birds are pursuing insects. Also, unlike the solitaires, 

 their voices are undistinguished and their nests are placed in bushes 

 and trees. 



KEY TO SPECIES OF PTILOGONATIDAE 



1. Yellow present on undersurf ace 2 



No yellow on undersurf ace 3 



2. Tail long, graduated, with white spots. 



Long-tailed Silky-flycatcher, Ptilogonys caudatus. p. 171 

 Tail not graduated, all black. 



Black-and-yellow Phainoptila, Phainoptila melanoxantha. p. 175 



3. Back dark blue-gray. 



Black-faced Solitaire, Myadestes melanops. p. 167 



Back bright reddish brown. 



Varied Solitaire, Myadestes coloratus. p. 169 



