PACKAno] THE SOCIAL LIFE OF INSECTS. 337 



to watching the progress of a predatory war of this kind 

 waged by one nest of barbara against another, and whicli 

 lasted for forty-six days, from January' 18 to March 4!" 

 These wars are usually the result of thieving expeditions. 



Tliis Atta barbara is said b}' IMoggridge to drill holes in 

 the rock, a fact not known to me until after the last chapter, 

 on Insects as Architects, was printed. ''In two cases," 

 sa3's our author, "I have found nests oi^ Atta barbara at 

 Mentone which were carried far into the living rock in 

 places where it happened to be of an even grain, and not 

 gritty or pebbly as it frequently is. It was quite by chance 

 that I first discovered this very interesting fact, having 

 tracked a train of seed-bearing workers to a part of the 

 sandstone rock where steps had quite recently been hacked 



out leading to some terraces At one point, where 



the rock was almost entirely solid and without tlaw or crev- 

 ice, and where it was clear that the passages were entirely 

 the work of the ants, we measured a tunnel b^' worming a 

 straw down into it, and found it to be ten inches in lengtli. 

 He subsequently traced this tunnel or rock gallery down 

 until it communicated with a chamber filled with Avinged 

 ants and seeds of several kinds. This granary was horizon- 

 tal, and merely an enlargement of an ordinary galler}' of 

 compressed spindle shape, flattened from above downwards, 

 measuring as nearly as I could estimate three inches in 

 length, by a trifle less than an inch in breadth, and half an 

 inch in height. The walls were tolerably smooth, but not 

 prepared or glazed in the way that certain small terminal 

 cells which I shall shortl^^ describe were." 



IMany more facts afforded by competent observers might 

 be adduced to throw light on the interior life of these ant 

 repul>lics. How perfecth^ each one does the work allotted 

 to it ; how equally the division of labor is carried out ; with 

 what admirable harmony and unity of purpose all work for 

 the common end, that end the preservation and maintenance 

 22 17 



