Todd-Carriker : Birds of Santa Marta Region^ Colombia. 99 



nimhe" (^humeralis meridana). The first may be briefly dismissed 

 as having been based on an error in identification in Dr. Allen's list 

 (later corrected by Dr. Allen himself). The case of Myospiza is no 

 doubt authentic, since this bird was taken by the junior author at 

 about the same elevation. It would seem to be a case where a Trop- 

 ical Zone species has followed up its natural habitat far above its 

 usual range, and is probably to be explained by the presence of savan- 

 nas on this slope within the confines of the Temperate Zone. Cinclus 

 rivularis and Brachyspiza capensis peruviana, on the other, hand, have 

 extended their range in the opposite direction, following their habitat 

 downward through the Subtropical Zone. 



The Paramo Zone. 



Character and Extent. — This zone, so extensive in the Andes of 

 Colombia, especially in the eastern and central cordilleras, is greatly 

 restricted in the Sierra Nevada de Santa Marta, and contains but few 

 typical forms. ^^ The conditions are practically the same as on the vast 

 paramos of the Andes, but on so small a scale that an extensive bird 

 fauna is an impossibility, this circumstance naturally not favoring the 

 development or maintenance of a large number or great variety of 

 forms. The ecological conditions obtaining in the Paramo Zone have 

 already been fully described in the chapter on that subject. We would 

 set the lower limit of this zone at about ii,ooo feet on the north slope 

 of the Sierra Nevada. The fact that the tree-limit lies s.o much lower 

 down here than it does in the Andes is responsible for several species 

 of this zone ranging more or less below this level, and min- 

 gling with the species of the Temperate Zone. It is hard to say, for 

 instance, whether Ramphomicron dorsale, Catamenia alpica, and Phry- 

 gilus unicolor nivarius are properly Temperate or Paramo Zone forms, 

 since they are known to range from g,ooo to i S,ooo feet, and they have 

 accordingly been allocated mainly by analogy. The upper limit of the 

 Paramo Zone is of course the snow-line, which here lies at about 

 15,000 feet, varying with the season up to 16,000 feet. • 



13 The area assigned to this zone on the map is obviously entirely too large 

 by comparison, in consequence of the inaccuracy of the map in question. 



