io8 IN THE GUIANA FOREST, 



Those living on the ground have the advantage 

 of being able to dart on their prey and coil round 

 it so quickly that the movement is hardly dis- 

 tinguishable. With their bodies coiled round a 

 branch this is not so easy to the tree-snake, and 

 we may therefore presume that the poison fangs 

 were originally developed to get over this difficulty. 

 It is true that there are many non-poisonous 

 species now living in trees, and a number of 

 venomous kinds at home on the ground, but it 

 can be easily conceived that the first development 

 may have taken place in an arboreal species. At 

 first sight the naturalist may be inclined to pity 

 these poor creatures, as they seem to have so 

 few weapons of defence, but when he studies 

 them a little more he is struck with their many 

 beautiful adaptations to circumstances. Without 

 proper teeth and entirely devoid of claws they 

 seem almost helpless, yet they exist, develop, and 

 show no signs of degradation, but, on the contrary, 

 appear to flourish to perfection. 



Lizards and frogs, like snakes, appear to have 

 been originally confined to the ground and water, 

 but in Guiana some species that live in the trees 

 are among the most interesting of our animals. 

 As in the case of other forms of life these show 

 marvellous adaptations to their environment, and 



