A NATURALIST IN BRAZIL 



from Mexico, and where it did great damage to the sugar planta- 

 tions. But in Ceylon, no later than 191 1, a planter showed me 

 with grim satisfaction a shrub which was absolutely leafless : it had 

 been attacked by a black fungus. It was reported from Honolulu 

 also that the shrubs had lost their leaves and flowers; and so the 

 Cambara will disappear in India just as the American Water- 

 hyacinth perished in Europe, though at first it grew so luxuriantly 

 in the ponds that the fish were stifled. 



This example shows how a Uttle human interference with a very 

 restricted area may affect the landscape of whole countries, inasmuch 

 as Nature may see to the wider distribution of the species introduced. 

 This should make us doubly careful of introducing alien species. 

 Many cases of transplantation have occurred involuntarily; seeds 

 have adhered to sacks, articles of clothing, etc. Thus, on the railway- 

 tracks in Sao Paulo I saw several of our native Hawkweeds, and 

 despite the sun our honeysuckle was blooming fragrantly among the 

 bushes. In northern Brazil the castor-oil plant, introduced from 

 India or Africa, was growing luxuriantly on every refuse-heap. 

 Even on the edge of the virgin forest this quickly-growing plant is 

 common everywhere (Plate 23). 



But it is one thing if individual plants find their way into a foreign 

 country, and quite another if a whole countryside is given an alien 

 character. 



The eucalyptus, it is true, grows with unusual rapidity, and 

 yields useful timber, but it is highly probable that among the 

 thousands of Brazilian species there are trees with the same qualities. 

 The eucalyptus is known also as the "fever tree" ; not because the 

 mosquitoes avoid it, for it has been observed that they thrive in 

 swampy eucalyptus woods, but because the tree draws a great deal 

 of water from the soil, which is quickly evaporated by the leaves, 

 and so the puddles in which the mosquitoes breed are dried up. 

 This quality, however, has its disadvantages in Brazil, for the forests 

 retain moisture, protect springs, and regulate the climate. Already 

 the Brazilian climate is beginning to change; the rains are not as 

 regular as they used to be, and here and there the country suffers 

 from drought. The explanation is that great areas of forest have 

 been destroyed; during the war, in particular, the timber in the 

 neighbourhood of the railway-lines was cut, as there were no imports 

 of coal, and even to-day the locomotives burn wood. 



This progressive deforestation is a serious matter, and if it is not 

 discontinued the future of Brazil will be at stake. The Mediterranean 

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