Naturis Militia 323 



cattle, which swariti upon every leaf and blade of grass, 

 except on the higher hills. 



To make matters worse, too, the mongoose was 

 imported a few years ago, and, like sundry other 

 importations, has proved a dismal failure. The idea 

 was that it would kill off the rats which so swarmed in 

 the sugar-plantations as to be a great nuisance to the 

 planters. And the mongoose began well ; but when 

 its numbers had increased, as they did enormously, it 

 began to vary its diet of rats by eating the eggs of such 

 birds as build on the ground, and then it went on to 

 eat the birds themselves, and even poultry, besides 

 killing off all the lizards and snakes, which were not 

 only quite harmless but most useful as insect-eaters. 

 In one way and another, the ticks were thus delivered 

 from their natural enemies, and now have things pretty 

 much their own way, and seem likely to have for some 

 time to come. 



Jamaica has given birds for ticks, and the Isle of 

 Bourbon made an almost worse exchange, for it gave 

 birds for grasshoppers. A price was put upon the heads 

 of the swallows, and they disappeared; but in their 

 stead came grasshoppers in such overwhelming swarms 

 that they took entire possession of the fields and 

 devoured everything. And the mischief did not stop 

 here — there was worse to follow ; for when the green 

 things were destroyed, the island became a prey to 

 scorching, biting drought. So dangerous is it to inter- 

 fere with the wise arrangements of nature, so utterly 

 impossible for any human contrivances to take their 

 place. 



In sandy deserts, birds are naturally almost wanting, 

 for there are few trees or bushes, and little vegetation 



