232 IN THE GUIANA FOREST. 



show the different conditions by their paucity of 

 leaves, hardness of stems, and brilliancy of colour- 

 ing. The shrubs too look poor and meagre, and 

 are more subject to the attacks of the blood- 

 sucking loranths, although even these pests cannot 

 succeed in forming such large and dense masses 

 as in other places. 



The vegetation here may be looked upon from 

 two points of view ; first, that which represents 

 it as an approach to the ancestry of the trees and 

 epiphytes of the forest ; and second, as a class 

 which has never succeeded in migrating beyond 

 its peculiar environment. As there are epiphytal 

 aroids and orchids, so there are also their proto- 

 types on the sand-reef, in some cases differing 

 considerably, and in others but little. The great 

 Anthurium of the tree-top is represented on the 

 sand-reef by a similar species, and one form of the 

 Catasetum tridentatum that grows on branches 

 beside the creek as closely resembles the Catasetum 

 discolor of the mourie. Excepting some of the 

 Clusias and figs, however, they generally differ 

 so much as to be ranked as distinct species, 

 showing considerable progress since the remote 

 time when the separation took place. Of the 

 second class the species of Paepalanthus, the 

 Schizseas, and a host of other dwarf wiry plants 



