Queer Friendships 



the ants draw the sugary liquid of which they are so 

 fond. Pictures have been painted of the ants imbibing 

 droplets from the tips of the tubercles. The fact remains, 

 however, that the tubercles are organs of defence, as the 

 following little experiment will show. If the grubs of 

 the lacewing fly are introduced to a colony of aphides 

 and carefully watched, it will be observed that the active 

 grubs at once proceed to attack their fellow-insects, which, 

 in fact, form their natural food. Aphis after aphis will 

 be seized in the grub's powerful jaws and sucked dry. 



Occasionally, if we watch carefully, we shall observe 

 that there is a hitch in the usual proceedings ; the aphis, 

 so to speak, gets in the first blow and discharges a sticky, 

 wax-like substance from its tubercles into the face of its 

 enemy. This substance hardens at once and forms a 

 veritable mask over the face of the aggressive grub, to 

 such an extent that it is forced to abandon its hunt till 

 it has cleaned itself, an operation which takes some con- 

 siderable time and permits of the aphis making good 

 its escape. Here we may notice a very interesting and 

 striking fact the aphides which habitually live in com- 

 pany with ants have either no tubercles or feebly developed 

 ones ; those which are not visited by ants have these 

 organs well developed. Why ? The ants afford protection 

 to the green-fly from their enemies so that it is unnecessary 

 for them to be provided with organs of defence. 



So far we have only mentioned the visits of ants to 

 stray colonies of aphides, but the relationship of these two 

 kinds of insects is often far more intimate. Some ants 

 actually farm certain aphides. The common aphis of the 

 Indian corn is a good example, so we will relate some of 

 the observed facts concerning this insect. The green-fly 

 eggs are laid in the autumn and are carried by the ants 

 into their underground nests ; here they are tended 

 throughout the winter ; they are moved about with great 

 care in order that they may be kept in suitable climatic 

 conditions. 



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