446 APPENDIX 



the broken lirnb of his comrade ; there is also quite a credible 

 story of a white horse who licked a wound made by a set on on 

 the chest of a companion which the latter could not reach owing 

 to his short halter. 



In contrast to these actual examples of mutual help, stands 

 the fact that parrots in their antipathy against those who are 

 sick, crippled or wounded, either of their own or some other 

 variety of bird, hunt them down and kill them. In this case, 

 according to Biichner, pity is extinguished by the stronger feel- 

 ing of abhorrence, and the condition must be regarded as an 

 exception to what is a very general rule among animals a rule 

 especially well marked among the gregarians. It is certain, says 

 Darwin, that animals living in communities have a feeling of love 

 for one another which is much less marked in those living solitary 

 lives. The feeling of pity, which is shown in various instinctive 

 actions, is taken by Darwin as the explanation of that heredi- 

 tary impulse which compels social animals to the exercise of 

 mutual helpfulness. 



Since instances of neighbourly help are especially to be found 

 in social animals, it is not surprising that these beginnings of 

 therapeutics should be especially observed in the insects which 

 dwell in communities. We know that these inhabitants of the 

 insect commonwealths are endowed with a brain, which, for all 

 its minute size, is of so fine a quality that it has been the wonder 

 of all students of nature. The ants stand highest in the series, 

 and among them examples of the treatment of the sick and 

 wounded have been reported which would seem incredible were 

 they not vouched for by competent observers such as Huber, 

 Forel, Lubbock and others. Ants take in other ants when sick 

 or wounded, provided that they belong to the same species, and 

 that the disease or damage is not too severe. In the latter case 

 they are regarded as hopeless, carried outside the ant-hill and 

 abandoned. But even in this there is, according to the reports 

 of the above-named observers, the greatest difference both in 

 willingness and in dexterity between different individuals. 

 Forel observed a colony of white ants (Formica pratensis) 

 while in the act of changing their place of abode. On the sum- 

 mit of the old nest an obviously sick ant was moving with 

 tottering steps, drooping antennae and half-closed jaws. Other 

 ants came up to it, stroked it and looked at it in various places 

 and tried gently to drag it inside the nest. Suddenly one of 



