PLANTS GUARDED BY ANTS 



These facts, startling as they may seem, are apparently quite 

 well authenticated and have not been seriously questioned. 



There are a great number of leaf-cutting ants who are, 

 indeed, amongst the most dangerous of the many insect pests 

 in South America and elsewhere. Wallace {Revue Scieri- 

 tijique^ 179, p. 29), in speaking of the Saauba or leaf-cutters, 

 describes how he placed a large heavy branch across the route 

 of one of their columns. 



The long line of laden ants was checked, and the greatest 

 confusion set in at the head of the column. Each ant, for 

 several feet down the column, then laid down its leaf, and all 

 set to work to tunnel under the obstacle. This was managed 

 in about half an hour's time, and the column then proceeded 

 on its way. 



Amongst other interesting land curious facts connected 

 with these extraordinary insects is that some kinds are 

 actually kept up by certain plants as a sort of standing army 

 or police. 



There are no less than 3030 species of plant which keep 

 these standing armies of ferocious ants, or if they do not 

 keep them, at any rate lay themselves out to attract them. 

 The kinds which are attracted live upon sugar, and are 

 strong, active, and extremely good fighters. When travelling 

 through the bush in Africa, it is not unusual in some places 

 to touch inadvertently one of these protected trees. In a 

 moment one''s hand and arm are covered by ants whose heads 

 are dug deep down into the skin, biting with all their strength. 



It is of course impossible to describe all the plants which 

 protect themselves against injurious insects and even large 

 animals in this way, but two of them must be mentioned. 



There are certain Acacias which are particularly inter- 

 esting. Like most of this order, they have large hollow 



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