262 NOCTURNAL LIFE OF ANIMALS 



primitive or primeval forest, as well as Urseit and Urvolk, 

 primitive age, primitive nation, are words of rather inde- 

 finite meaning, and, for the most part, only relative import. 

 If this name is to be given to every wild forest full of 

 a thick growth of trees on which Man has never laid a 

 destroying hand, then the phenomenon is one which 

 belongs to many parts of the temperate and cold zones. 

 But if the character of the " Urwald" is that of a forest 

 so truly impenetrable, that it is impossible to clear with 

 an axe any passage between trees of eight or twelve feet 

 diameter for more than a few paces, then such forests 

 belong exclusively to the tropical regions. Nor is it by 

 any means, as is often supposed in Europe, only the 

 interlacing " lianes" or climbers which make it impossible 

 to penetrate the forest; the "lianes" often form only a 

 very small portion of the underwood. The chief obstacle 

 is presented by an undergrowth of plants filling up every 

 interval in a zone where all vegetation has a tendency 

 to become ligneous. An impatient desire for the fulfil- 

 ment of a long cherished wish may sometimes have led 

 travellers who have only just landed in a tropical country, 

 or perhaps island, to imagine that although still in the 

 immediate vicinity of the sea-shore they had entered the 

 precincts of a primeval forest, or " Urwald," such as I 

 have described as impenetrable. In this they deceived 

 themselves ; it is not every tropical forest which is entitled 

 to a$ appellation which I have scarcely ever used in the 

 narrative of my travels ; although I believe that of all 

 investigators of nature now living, Bonpland, Martius, 



