in ANIMAL LIFE IN THE TROPICAL FORESTS 301 



undoubtedly tend to concealment; but we have also the 

 strange phenomenon of white forest birds in the tropics, a 

 colour only found elsewhere among the aquatic tribes and in 

 the arctic regions. Thus, we have the bell-bird of South 

 America, the white pigeons and cockatoos of the East, with 

 a few starlings, woodpeckers, kingfishers, and goatsuckers, 

 which are either very light - coloured or in great part pure 

 white. 



But besides these strange and new and beautiful forms 

 of bird life, which we have attempted to indicate as charac- 

 terising the tropical regions, the traveller will soon find that 

 there are hosts of dull and dingy birds, not one whit different, 

 so far as colour is concerned, from the sparrows, warblers, 

 and thrushes of our northern climes. He will, however, if 

 observant, soon note that most of these dull colours are pro- 

 tective; the groups to which they belong frequenting low 

 thickets, or the ground, or the trunks of trees. He will find 

 groups of birds specially adapted to certain modes of tropical 

 life. Some live on ants upon the ground, others pick minute 

 insects from the bark of trees ; one group will devour bees 

 and wasps, others prefer caterpillars ; while a host of small 

 birds seek for insects in the corollas of flowers. The air, the 

 earth, the undergrowth, the tree-trunks, the flowers, and the 

 fruits, all support their specially adapted tribes of birds. 

 Each species fills a place in nature, and can only continue to 

 exist so long as that place is open to it ; and each has become 

 what it is in every detail of form, size, structure, and even of 

 colour, because it has inherited through countless ancestral 

 forms all those variations which have best adapted it among 

 its fellows to fill that place, and to leave behind it equally 

 well adapted successors. 



REPTILES AND AMPHIBIA 



Next to the birds, or perhaps to the less observant eye 

 even before them, the abundance and variety of reptiles form 

 the chief characteristic of tropical nature ; and the three 

 groups lizards, snakes, and frogs comprise all that, from 

 our present point of view, need be noticed. 



