LIST OF FIGURES IN TEXT. 



Fig. i. Range of Richmondena phcenicea, a characteristic species of 

 the Arid Tropical Zone of Venezuela, but which does not pass 

 beyond the Goajira region in Colombia 71 



Fig. 2. Range of Microrhopias intermedia (1), a species of the Arid 

 Tropical Zone which enters the Santa Marta region from the east, 

 but is replaced in the Magdalena Valley by an allied form, M. 

 alticincta hondec (2) 72 



Fig. 3. Range of Thamnophilus nigriccps, a species of the Humid 

 Cauca-Magdalena Fauna which reaches the Santa Marta region 

 from the south yy 



Fig. 4. Range of Phcugopedius lectus (1), a species peculiar to the 

 Santa Marta region, and of its probable antecedent, P. rutihis 

 (2) 79 



Fig. 5. Range of Phacthornis longirostris susurrus (1), a characteristic 

 form of the Humid Tropical Zone of the Santa Marta region, 

 and of its nearest ally, P. longirostris cephalus (2), to show their 

 discontinuous distribution 80 



Fig. 6. Discontinuous range of Aulacorhynchtis calorhynchus, a Sub- 

 tropical Zone species found in the Venezuelan Andes and the Sierra 

 Nevada de Santa Marta 88 



Fig. 7. Range of Xenicopsis montanus striaticollis (1), X. montanus 

 venezuelanus (2), and X. montanus anxius (3), to show the de- 

 velopment of a distinct Subtropical Zone form in the coast range 

 of Venezuela and in the Sierra Nevada de Santa Marta respec- 

 tively u 92 



Fig. 8. Ranges of the northern forms of Octhodiccta, a genus of the 

 Temperate Zone with a representative each in the Colombian Andes, 

 the Venezuelan Andes, and the Sierra Nevada de Santa Marta. 

 (1) O. fumigata; (2) O. lugubris; (3) O. pernix 97 



Fig. 9. Range of Oxypogon, a genus of the Paramo Zone, to illustrate 

 the breaking up of the group into distinct species in the several 

 parts of its range. (1) O. stuebelii; (2) O. guerinii; (3) O. 

 lindenii; (4) O. cyanolccnnis 101 



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