150 A NATURALIST IN THE GUI AN AS 



alight on some low shrub whence they perform the 

 same operation repeatedly. The movements of some of 

 these thrushes are so quick that it is difficult to follow 

 them. In the stomachs of those birds I shot I found 

 fragments mostly of soft-bodied insects such as moths 

 and crickets. In spite of the vast numbers of various 

 kinds of insects destroyed by the combined efforts of the 

 ants and birds, these tropical forests teem with an insect 

 life which appears to suffer no diminution. 



To the inquirer into the marvellous ways of Nature 

 nothing can be more interesting than to compare the 

 habits of various animals with those of the most highly 

 developed of them all — man. The Guaco is the solitary 

 hunter relying on himself alone, cunning and relentless, 

 and with an insatiable thirst for slaughter. In the flocks 

 of rice-birds who have learnt how to make use of sentries 

 in order to guard against surprise while they are com- 

 mitting their depredations, we have an instance of an 

 understanding such as exists between the members of 

 small savage tribes for mutual protection. The densely 

 peopled colonies of Parasol Ants, with their foragers and 

 growers of food, are the counterparts of those civilised 

 communities where each person follows some particular 

 occupation with the view of obtaining greater skill in 

 special branches than if the same individual had to 

 undertake a variety of employments. Everyone who has 

 read 'The Naturalist in Nicaragua' will remember Mr. 

 Belt's exhaustive account of the habits of these and other 

 ants of the tropics, in which he concludes as follows : 

 ' When we see these intelligent insects dwelling together 

 in orderly communities of many thousands of individuals, 

 their social instincts developed to a high degree of per- 

 fection, making their marches with the regularity of 



