4 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. Ill 



The race serus ranges from the Amazonian forest and its outliers 

 (from Para in the east, and in the west from the Rio Purus and 

 Rio Jurua, from Mato Grosso (Sao Luiz de Caceres) and from Santa 

 Cruz in BoHvia) northward to Peru, Ecuador, Colombia, Surinam, 

 Venezuela, Central America, and Mexico. 



In Spisaetus ornatus, which, as a species, seems to have a range 

 geographically and ecologically very similar to that of 6". tyrannus, 

 the northern race vicarius occurs from southern Mexico, south across 

 Central America to Colombia west of the eastern Andes, and western 

 Ecuador, possibly to Peru, while typical ornatus is found from Vene- 

 zuela and the Guianas southward across Brazil to Bolivia and Para- 

 guay. In Spisaetus ornatus it looks as though the Andes constituted 

 a possible barrier between the component forms, whereas in S. 

 tyrannus this is not the case. 



