1917.] Chapman, Distribution of Bird-life in Colombia. 85 



Bogota and Fusugasuga. The first-named locality has a highly developed 

 Temperate Zone life; while at the second, the fauna of the Subtropical Zone 

 is equally well represented. 



A study of the bird-life of the Colombian Andes, shows, therefore, that 

 it is distributed in four zones, and since the lower zone lies wholly within the 

 tropics it follows that the remaining zones are all altitudinal. While I 

 have been tempted to use names for them which seemed especially descrip- 

 tive locally, it has been deemed far more desirable to accept existing terms 

 which are generally applicable. These zones with their altitudinal bounda- 

 ries are as follows: 



Tropical Zone sea-level to 4500-6000 ft. 



Subtropical Zone 4500-6000 ft. to 9000-9500 ft. 



Temperate Zone 9000-9500 ft. to 11,000-13,000 ft. 



Paramo Zone 11,000-13,000 ft. to snow-line (15000 ft.). 



These divisions correspond to the 'Tierra Caliente,' 'Tierra Templada,' 

 'Tierra Fria,' and 'Paramo' of other authors, but the altitudes here given 

 are higher than those based on temperature alone. 



Basing the limits of his divisions upon an apparently purely arbitrary 

 assignment of isotherms to zonal boundaries, Hettner i places the upper 

 limits of the Tierra Cahente [= Tropical Zone] at 1000 metres; the Tierra 

 Templada [= Subtropical Zone] between 1100 and 2000 metres; the Tierra 

 Fria [= Temperate Zone] between 2100 and 3000 metres, and the Paramo 

 between 3100 and 4000 metres. It will be observed that the limits of only 

 the upper zone conform to those determined on the distribution of bird-life. 

 It is reassuring, therefore, to find a much closer agreement between the 

 zonal boundaries here given, based on the distribution of birds, and those 

 based upon the distribution of vegetation presented by Wolf,^ who, as a 

 result of his studies of the flora of Ecuador, gives for both the Western and 

 Eastern Andean slope four zones of life as follows : 



Tropical sea-level to 1600 metres. 



Subtropical 1600 to 3000 metres. 



« Subandine [= Temperate] 3000 to 3400 metres. 



Andine or Paramo 3400 to 4600 metres. 



The limits of the two lower zones, for which Wolf employs names I had 

 independently adopted, are essentially the same as those I here give for 

 Colombia. The third, which Wolf calls the Subandine, but for which a 

 continental-wide view of the subject suggests the name of Temperate Zone 



1 Kordillere von Bogota, p. 70. 



2 Geographia y Geologia de Ecuador, p. 435 et. seq. 



