THE TROPICAL ZONE. 221 



humidity of the atmosphere, the heavy dews of the dry 

 season, and the continuous rains which fall at other times, 

 combined with the heat of a tropical sun, with such plants 

 as Tillandsias, Melastomacete, Cactuses, Orchises, Ferns, etc., 

 all in the vigour of life ; what luxuriance then must be the 

 result, when a rich soil, and moisture and heat, are all united ! 



But let us wander a little way from the town of Rio de 

 Janeiro, and judge for ourselves let us leave the sea-shore 

 and its curious Mangrove-trees (Plate XIII.) and Avicen- 

 nias (A. tomentosa, which, though belonging to a different 

 family, the Brazilians call White Mangroves, on account of 

 a similarity of habit) let us leave these sea-shore sights 

 and the level marshy ground let us leave the noisy streets 

 behind us, and make our way to the rich valley at the foot 

 of the Corcovado Mountain, and wander up to the terrace- 

 like level, along which the water of the aqueduct is brought 

 from its source. The hedges near the town are gay with a 

 scrambling kind of shrub called Bougainvillea Brasillensis, 

 the flowers of which are concealed within large rose-coloured 

 bracts. It was first discovered by Commerson, and named 

 by him in honour of his commander. 



As we are apt to regret sometimes the custom of imposing 

 Latinized names of persons on newly found flowers, it may 



