EPIPHYTES AND PARASITES 



ground too is often covered with them. The Bromelias have a rich 

 and sumptuous appearance, and their flowers add greatly to the 

 beauty of the forest. In many varieties the inner side of the leaves 

 is red in colour, and the great bell-shaped flowers grow from their 

 midst. Others have red or yellow corollas, and some produce a tall 

 spire of yellow trumpet-flowers, each enclosed in a bright red 

 calyx. The Coral Gravata surprises the beholder by a sort of coral 

 staff", round the handle of which are lateral twigs bearing little red 

 clubs with violet tips. 



The most useful of the Bromelias are the Ananas or Pineapples, 

 which are native to South America. Those of Pernambuco, known as 

 Abacaxi, are the sweetest and juiciest of all, and have the finest aroma. 



The epiphytic Bromelias store up water in a way of their own. 

 They do not, like some of the Orchids, use their roots for this purpose ; 

 their first duty is to anchor the plant firmly to the supporting bough, 

 and they do this in many ways, sometimes even secreting a kind of 

 cement, so that they are able to adhere to the smoothest surfaces — 

 for example, to naked cliffs — and there prepare the soil for other 

 plants. The leaves are the Bromelia's reservoir. These become thick 

 and fleshy, and have a tough, leathery outer skin, which prevents 

 evaporation from the juicy tissues. 



But the Bromelias do not merely store water in their thick leaves ; 



they also form regular basins which catch and hold rain-water. 



Where the leaves of the rosette come together — that is, at their 



root — they are flattened, and their edges are raised, so that the 



widened portion is spoon-shaped. Here the water is caught and 



stands, and since all the leaves form a closed circle, a regular pot 



or basin is produced, which contains a considerable amount of 



water. If one tears off" a leaf one is deluged with water, often 



amounting to a couple of pints. In these miniature pools there are 



small crustaceans, predatory insects, salamanders, and even fish, 



and a special "Gravata frog," a little creature two-fifths of an inch 



in length. And always, in the reservoirs of the Bromelias, we find 



the larv« of the mosquito, wriggling up and down, and living in 



this natural aquarium until the insects emerge from their pupae and 



take to the air. During the construction of the Panama Canal many 



of the workmen engaged on one particular stretch suffered from 



fever. Since no pools or puddles could be found, and since the 



carrier of the disease, the mosquito, can breed only in water, no 



one could understand where the fever came from until someone 



observed the reservoirs of the Bromelias. 



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