^"I'g^^n ^°^ Ihering, Biology of the Tyrannidce. ^I^ 



the very striking and beautiful coloration is found only in the 

 adult males, while the females and young males retain uniform 

 olive colors, and it is also only among the adult males that we 

 meet with such abnormal characters as enlarged stems of the pri- 

 maries and secondaries, erect frontal feathers, and elongated tail- 

 feathers, while the Ptilochlorinse resemble the Elaineinae not only 

 in coloration, but also in the rather small and bristled bill. These 

 facts induce us to conclude that the Pipridee and Tyrannidae have 

 descended from a common ancestral form, the nearest relatives of 

 which are the Elaineinje among the Tyrannidffi with the Ptilochlo- 

 rinae among the Pipridae. The common ancestors must have been 

 birds of small size, with pronounced syndactylism of the outer 

 toes, with rather small, somewhat compressed and bristled bill, 

 and of uniform olive color. The frequent occurrence of a yellow 

 coronal patch among the Pipridae as well as the Tyrannidge leads 

 us to suppose that this ornament may have been transferred from 

 the common ancestors, which were inhabitants of the woods. 

 From the Elaineine branch of the Tyrannidae originated, besides 

 the Euscarthminae and Serphophaginae, whose biological conditions 

 are nearly the same, two great sections of inhabitants of the 

 campos, mostly large-sized birds, the Taeniopterinae and the Pit- 

 angine-Tyranninae. 



With these general results the geographical distribution accords. 

 As is generally the case with the wood-inhabiting birds, the dis- 

 tribution of the Elaineinae of Brazil is a somewhat restricted one. 

 While a number of species are distributed through the forest region 

 of Brasil, only a few range through Guiana and Central America 

 to Mexico. The Euscarthminae in this respect also do not diverge 

 much from the Elaineinae, but the Serphophaginae, preferring 

 open plains and river banks, do occur not only in the campos 

 but the majority of them is restricted to the Andine Region. 

 These two groups of campos inhabiting Tyrannidae are wholly 

 different not only in their way of life but also in their geographical 

 distribution. 



The habits of the Tainiopterina; are terrestrial. They run on 

 the ground and have in relation therewith elongated tarsi and 

 strong ambulatorial feet, seeking their insect food on the ground. 

 They inhabit the pampas and the campos of central Brazil, being 



