■2 20 Von Ihering, Biology of the Tyrattnidcs. Lj"ly 



represented in the littoral zone by but few species. On the other 

 hand, many species and genera are adapted to live in the Andes, 

 where they occur from Patagonia to Colombia, but no species of 

 these Andine forms passes into Mexico and Texas. For this rea- 

 son I think it to be right to separate the genus Sayornis from the 

 Taeniopterin^e, and to unite it to the Tyranninae, in the society of 

 which it is found in North America and from which it does not 

 differ regarding its biology. 



The Pitanginae and Tyranninee, on the contrary, are of very wide 

 geographical distribution. Though preferring the campos, they 

 avoid the treeless plains. They are not ground-walkers, but cap- 

 ture insects as they fly like Flycatchers. They are very active, 

 courageous birds of large size and good flight, and their geograph- 

 ical distribution therefore, as a rule, is very wide, some of them 

 occurring from Argentina to North America. Among the seventy- 

 eight species of Tyrannida; living in the State of S. Paulo forty- 

 three belong to the Elaineinae and the allied groups of arboreal 

 life, and of these ten, or 23 per cent, have a relatively wide geo- 

 graphical distribution. Among the six Pitanginae only the two 

 species of Conopias and Sirystes are restricted to Brazil, while the 

 species of Legatus, Myiozetetes, Pitangus, and Myiodynastes are 

 represented even in the southern parts of North America by the 

 same species or by little different local races. Among the sixteen 

 Tyranninffi of S. Paulo all have a very extensive geographical 

 distribution except Blacicus cinereus (Spix) and Tyrannus albo- 

 gularis Burm., so that more than 80 per cent of the Pitanginae 

 and Tyranninae of S. Paulo have very wide geographical 

 distribution. 



These facts of geographical distribution show us that the only 

 system of nomemclature well applicable to the discussion of zoo- 

 geographical problems is the trinomial. 



The use of binomials as employed in the excellent Hand-list of 

 Dr. Bowdler Sharpe may be more advantageous for collection 

 purposes, but it combines in a very inconvenient manner well- 

 defined species with local races. Such facts as the vast distribu- 

 tion of Pitangus sulphuratiis (L.) and Myiozetetes similis (Spix) 

 are completely hidden by the use of binomial nomenclature. 



It is also among these birds that we meet true migratory forms, 



