Birds of Cameroon Alouniain. 475 



quote the following: — '^This noble group attains 13,100 

 feet o£ elevation, and consists of many peaks, all of volcanic 

 origin, crowning an irregular short littoral range. From 

 Mr, Mann's* descriptions, the Cameroons Mountains pre- 

 sent a dense forest region up to about 7000 feet, when, open 

 grassy fields succeed, with bushes of Hypericum, Pittosporum, 

 Adenocarpus, Pygeum, Leucotho'e, Eincinella, Myrica, and 

 various herbaceous plants. The many peaks Avhich rise 

 above this elevation are either stony and barren (being all 

 formed of lava, scoriae, and basalt), or are dotted with tufts 

 of grass and a few other herbaceous plants.'^ 



Sir Joseph Hooker adopted the altitude of 5000 feet as 

 the lower limit of the temperate flora, because both on the 

 Cameroon and Fernando Po Mountains the temperate forms 

 preponderated at that elevation ; he goes on to say : — " In 

 these mountains, however, as in all other tropical ones, on 

 the one hand tropical genera and species ascend to this and 

 to much greater elevations, and on the other some temperate 

 forms descend considerably lower than their respective 

 temperatures would lead us to expect. This is partly owing 

 to the very varied conditions of exposure, humidity, and 

 temperature which may be found at the same elevation in 

 a mountain region traversed by gorges and ridges, and still 

 more to the equable annual temperature favouring both 

 the ascent of the tropical forms and the descent of the 

 temperate.'^ 



How far this state of things affects the bird population of 

 Cameroon Mountain it is hard to say, but it is certain that 

 many forms which are dealt with in the following pages 

 are confined to one of the three main belts of vegetation : — 

 The forest, the tree-fern, or the grass-country. 



The main features of Cameroon Mountain may be described 

 as follows : — 



1. Sea-level to 3000 ft. : apparently well wooded ; but a 

 certain amount of clearing has taken place. 



2. 3000 to 7000 ft. : dense forest. 



* A renowned botanical collector. 

 SER. X. VOL. III. 2k 



