Social Insects. 23 



fertilized autumnal queen from the worker generations, the for 

 mer being considerably larger and presenting even more marked 

 differences from the worker than occur in the similar states of the 

 bee. With Polisites, however, the difference between the fertilized 

 queen and the summer broods of workers is much less marked, 

 and it is more difficult to distinguish them. The abdomen 

 of the true queen of Polistes is somewhat longer and larger than 

 that of the worker, but the variation is so slight that accurate 

 separation is usually impossible, and there is probably less 

 difference between the worker and the fertilized female than ob 

 tains with the social bees, the worker being quite capable, in 

 many cases at least, of producing eggs which will develop into 

 other workers, and at the proper season also, doubtless, into males. 

 The distinction between the summer broods and the autumnal 

 females which are fertilized and hibernate, is probably produced 

 by food conditions, as in the case of bees, although accurate ob 

 servations are wanting. 



Just as in the case of bees, the study of the wasp family ( Vespidse) 

 in its different genera and species, reveals every gradation in habit, 

 from the solitary species to the more highly organized or social 

 forms, and these differences in habit are accompanied by differ 

 ences in structure, so that the origin of the higher or more social 

 forms may be traced through the less specialized. 



Many instances might be cited in illustration of the great in 

 telligence of wasps, and especially in proof of their wonderful 

 sense of direction. On the whole they exhibit a rather higher de 

 gree of intelligence than do the bees, in the remarkably varied pro 

 visions which they make for their young. Their habitations, also, 

 complete in themselves, and built chiefly of extraneous matter 

 not secreted from their own bodies, indicate greater architectural 

 dexterity than is found in the bees. 



ANTS. 



Few insects have attracted more attention, or have become more 

 renowned than the ants. Considering their comparatively di 

 minutive size, their endless activity, and the wonderful results 

 they accomplish, this is not to wondered at. 



Up to the present time some fifteen hundred species of ants 

 have been described, the great majority of the species, as well as 

 the largest and most rapacious, occuring in tropical and semi- 



