526 THE TROPICAL WORLD. 



enormous forest lands and river basins have never yet been visited by a naturalist, — 

 tbat the vegetation of the greater part of Central Africa is still completely hidden in 



FOREST ON THE PANAMA RAILROAD. 



mystery, — that no botanist has ever yet penetrated into the interior of Madagascar, 

 Borneo, New Guinea, South-western China, and Ultra-Gangetic India, — and that, 



