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the west coast of Colombia north of the Patia River. Reaching western 

 Ecuador, before the Loja region had attained its present altitude, they have 

 also advanced westward around the northern end of the Andes in Colombia, 

 but have not as yet completed their distribution either by ranging north- 

 ward from Ecuador or southward from northern Colombia. 



Fig. 6. Distribution of the western races of Manacus manacas. Illustrating the apparent absence 

 on the Pacific coast north of the Patia River of a conunon, widely distributed Amazonian species 

 which is found in western Ecuador and northern Colombia. 



1. Manacus manacus manacus. 2. Manacus manacus purus. 3. Manacus manacus interior. 



4. Manacus manacus abdiiivus. 5. Manacus manacus flaveolus. 6. Manacus manacus bangsi, 



7. Manacus manacus melanochlamys. 



