THE WEB OF LIFE 349 



fibre, but the social life improves upon this up to a certain 

 point. Every one knows how much the mind of adult 

 man is a social product. 



Another advantage that must mean much is bound to 

 accrue when there is any sort of permanent product which 

 is handed on from generation to generation as a sort of 

 external heritage. The loosely built ant-hill, the hard 

 edifice of the termitary, the honeycomb of the bee, express 

 a sort of communal art and a registration of achievement, 

 and must be of importance in the continuance of the social 

 life. In the more intelligent types there is probably some- 

 thing in the way of social tradition which secures a persist- 

 ent strategy, as when beavers cut a long canal through an 

 island or gradually build up a very strong dam. 



The defensive value of social organization is very well 

 illustrated in the case of many of the ants. In reference 

 to the South European harvesting ants (Atta structor and 

 Atta barbara) Mr. Moggridge noticed that their enemies 

 treated them with great circumspection. Lizards eat 

 only the winged males and females and try to keep out of 

 the way of the workers, who in their turn do their best to 

 be an effective bodyguard to the winged forms. There is 

 a large proportion of soldiers, some of which are literally 

 walking jaws, always ready to snap and to hold on to the 

 death. Of another enemy, the Tiger-beetles (Cicindela), 

 it is said that although they devour the workers, they keep 

 out of the way of the main body and look after the stragglers 

 only. If they fail to catch the ant at the strategic point, 

 just behind the neck, they are said to let go at once, as if 

 they were aware that if the ant's jaws once close on any 

 part of their limbs or feelers they will not leave go again, 

 even after death. 



