CHAPTER XIV 



QUEER FRIENDSHIPS 



IN the animal world there are very many examples of 

 the most extraordinary friendships ; animals of the most 

 diverse kinds live together, wholly or partially, and 

 usually to their mutual benefit. This friendship or 

 commensalism, as it is called by naturalists, reaches its 

 highest development among the ants. These social 

 insects are surrounded, either designedly or accidentally, 

 by more friends and cadgers than any other insects ; 

 moreover, they have domesticated some of these outsiders. 

 Green-fly, scale insects, tree-hoppers, lantern-flies, jumping 

 plant lice and caterpillars of the well-known " blues " are 

 all kept by ants as man keeps his cattle. 



Let us study an ant farm wherein green-fly or aphides 

 are the cattle. These insects make ideal cattle for ants 

 by reason of the fact that they live huddled together at 

 close quarters and are not very active, especially in their 

 wingless stages. The aphides attack practically all plants 

 except ferns ; some live on leaves, some on stems, others 

 on roots. Most of them live on the surfaces of plants, 

 but a few inhabit galls of their own making and therefore 

 are out of reach of the would-be farmers. The habits 

 which render these insects so accessible to ants also 

 expose them to a host of enemies, but of these more anon. 

 Green-flies are one and all armed with sharp pointed beaks 

 or rostrums with which they pierce plant tissues and suck 

 up the juices. These watery juices contain sugar, of which 

 a very small portion is retained by the green-fly and a 

 large portion is voided as excrement. 



The dried excrement is known as " honey dew " and, 

 being sweet, is much sought after by the ant, or even by 



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