dependently in all four of 

 these groups, and that suck 

 resemblances as they exhibit 

 are due more to what biolo- 

 gists call convergence than to 

 blood relationship. 



Ants are to be found every- 

 where, from the arctic regions 

 to the tropics, from timberline 

 on the loftiest mountains to 

 the shifting sands of the dunes- 

 and seashores, and from the 

 dampest forests to the driest 

 deserts. Not only do they 

 outnumber in individuals all 

 other terrestrial animals, but 

 their colonies even in very 

 circumscribed localities often 

 defy enumeration. Their col- 

 onies are, moreover, remark- 

 ably stable, sometimes outlast- 

 ing a generation of men. 

 Such stability is, of course, 

 due to the longevity of the in- 

 dividual ants, since worker- 

 ants are known to liv<^ i-om 

 four to seven and qui ens 

 from 13 to 15 years. In all 

 these respects the other social 

 insects are decidedly inferior. 



A GREAT PRODUCER OE SPECIES- 



Not only are the colonies 

 of the wasps and bumblebees 

 of rather rare occurrence, 

 but they are merely annual 

 growths. The honey-bees, too, 

 are very short-lived, the work- 

 ers living only a few weeks or 

 months, the queens but a few 

 years. The termites, though 

 perhaps longer-lived than the 

 Showing the arrangement of the chambers and galleries bees and wasps, are practically 



and the ants' method of classifying the brood according - - . ^ . . 



to stages. The lowermost chamber contains only cocoons 



(pupae), the next above mature larvae, while the young larvae 



and eggs are in the superficial chambers. 



INTERIOR OE AN ANT NEST OR EORMICARY (aETER 

 ERNEST ANDRE) 



ter into severe competition not only with 

 other organisms, but also with the mem- 

 bers of their own species, to whom they 

 are, moreover, bound by indissoluble ties. 

 There are two main groups of social 

 insects, the termites and the social Hy- 

 menoptera, the latter embracing three 

 minor groups, the social wasps, the social 

 bees, and the ants. It is more than prob- 

 able that social habits were developed in- 



confined to very definite lo- 

 calities in the tropics. Only 

 a few of the species have been 

 able to extend their range inta 

 temperate regions. 



Thus unquestionably the most success- 

 ful and dominant of all these groups is the 

 ants, for these have produced the great- 

 est number of species, have occupied all 

 parts of the earth, except the very tops- 

 of the high mountains and the cold arctic 

 and antarctic regions, with untold multi- 

 tudes of individuals, and have developed 

 the most intimate and complicated rela- 



732 



