566 THE TROPICAL WORLD. 



To be cultivated to advantage, the coffee-tree requires a climate where the mean 

 temperature of the year amounts to at least 68, and where the thermometer never 

 falls below 55. It is by nature a forest tree requiring shade and moisture, and thus 

 it is necessary to screen it from the scorching rays of the sun by planting rows of um- 

 brageous trees at certain intervals throughout the field. These also serve to protect 

 it from the sharp winds which would injure the blossoms. It cannot bear either 

 excessive heat or a long-continued drought ; and where rain does not fall in sufficient 

 quantity, artificial irrigation must supply it with the necessary mojsture. From all 

 these circumstances it is evident that the best situations for the growth of coffee are 

 not the sultry alluvial plains of the tropical and sub-tropical lands, but the mountain 

 slopes to an elevation of 4,500 feet. 



Like every other plant cultivated by man, the coffee-tree is exposed to the ravages 

 of many enemies. Wild cats, monkeys, and squirrels prey upon the ripening berries, 

 and hosts of caterpillars feed upon the leaves. Since 1847 the Ceylon plantations 

 have been several times invaded by swarms of the golunda, a species of rat which 

 inhabits the forests, making its nest among the roots of the trees, and, like the lem- 

 mings of Norway and Lapland, migrating in vast numbers when the seeds of the 

 nilloo-shrub, its ordinary food, are exhausted. " In order to reach the buds and 

 blossoms of the coffee, the golunda eats such slender branches as would not sustain its 

 weight, and feeds as they fall to the ground ; and so delicate and sharp are its incisors, 

 that the twigs thus destroyed are detached by as clean a cut as if severed with a 

 knife. The Malabar coolies are so fond of its flesh that they evince a preference for 

 those districts in which the coffee plantations are subject to its incursions, frying the 

 rats in oil or converting them into curry." 



Another great plague is the Lecanium cojffece, known to planters as the coffee bug, 

 but in reality a species of coccus, which establishes itself on young shoots and buds, 

 covering them with a noisome incrustation of scales, from the influence of which the 

 fruit shrivels and drops off. A great part of the crop is sometimes lost, and on many 

 trees not a single berry forms from the invasion of this pest, which was first observed 

 in 1843 on an estate at Lapalla Galla, and thence spreading eastward through other 

 plantations, finally reached all the other estates in the island. No cheap and effectual 

 remedy has as yet been found to stay its ravages, and the only hope is that, as other 

 blights have been known to do, it may wear itself out, and vanish as mysteriously as 

 it came. 



Mrs. Agassiz* gives an interesting description of the larva of the Brazilian coffee moth : 

 " For some time Mr. Agassiz has been trying to get living specimens of the insect so 

 injurious to the coffee-tree, the larva of a little moth akin to those which destroy the 

 vineyards of Europe. At last he succeeded in obtaining some, and among them was 

 one just spinning his cocoon on the leaf. We watched him for a long time with the 

 lens as he wove his filmy tent. He had arched the threads upwards in the center, so 

 as to leave a little hollow space into which he could withdraw. This tiny vault 

 seemed to be completed at the moment we saw him, and he was drawing threads for- 

 ward and fastening them at a short distance beyond, thus lashing his house to the leaf, 

 as it were. The exquisite accuracy of the work was amazing. He was spinning the 

 thread with his mouth, and with every new stitch he turned his body backward, 



* Journey in Brazil, 118. 



