22 Ants m Relation to Flowers. [Sess. 



of particularly good nectar. Certain warlike species of Ant 

 have found this out, and when the time comes they take 

 possession of the capitulum, feeding there to their heart's 

 content. One member of the party mounts to the top to act 

 as sentinel, and when he descries the approach of the enemy 

 he signals to the guard to turn out. This they do by holding 

 on to the bracts with their middle pair of legs, and keeping 

 their jaws ready to inflict a wound, and their abdomen ready 

 to squirt formic acid into it. So, if the beetle incautiously 

 comes too near, he soon has to leave with, so to speak, tears in 

 his eyes. Directly the critical period is past no more nectar 

 is given off by the bracts, the Ants take their leave, and the 

 flower blooms on in ordinary course. 



In reflecting upon these facts one cannot refrain from 

 speculating upon the relative intelligence — if such a term is 

 allowable — of Ants as compared with Plants. What we are 

 considering is, of course, not so much cases of intelligence in 

 the sense commonly understood, as that habit of adapting 

 themselves to new conditions which both organisms show. In 

 a certain way this may be regarded as a manifestation of in- 

 telligence, but it is of that kind which, instead of responding 

 within a very short space of time to unwonted circumstances, 

 takes many centuries, as it were, to think the matter out. 



What we are really dealing with is, of course, only a case of 

 Natural Selection and the Survival of the Fittest. But the 

 results may be regarded, as I have treated them here, as if 

 they had arisen at the will of the individual, and had been 

 brought about in its own lifetime, instead of being, as 

 they are in the great majority of cases, simply the aggre- 

 gate result of a long series of slight modifications in habit 

 and form which have proved beneficial to the species and 

 not to the individual. 



In the discussion which followed the delivery of this 

 Address, Mr Gloag mentioned a case he had met with in 

 Forfarshire, in which a considerable number of plants of 

 Dianthus deltoides harboured, each of them, a colony of Ants at 

 their roots. The plants were thriving remarkably well. There 

 were no Ant colonies at the roots of other plants growing 

 near. Has the formic acid any chemical effect upon the con- 



