THE NEW EVOLUTION 



(fig. 13, p. 2.1) made of various substances bound to- 

 gether with a web of silken threads. For instance, 

 the caterpillar of the common clothes-moth makes a 

 little tubular jacket for itself out of hairs cut from 

 your furs or woollen clothes. The larvas of the cad- 

 dis-flies, which live in water, make somewhat similar 

 coverings out of sticks or parts of leaves or sand 

 grains. Very many insects construct an elaborate 

 cocoon, which may be waterproofed inside, as a pro- 

 tection during the pupal stage. 



Many youthful insects, as the larvas of certain lace- 

 winged flies and the caterpillars of some lyca^nid 

 butterflies, cover themselves with the empty skins of 

 the aphids or other insects they have eaten or with 

 foreign substances which they impale upon or en- 

 tangle among their spines. This may be primarily 

 for the purpose of concealment or deception, but in 

 many cases it seems to be simply for adornment. At 

 any rate, the larva of a lace-winged fly or the cater- 

 pillar of an aphid-feeding butterfly draped in dead 

 aphids' skins strongly brings to mind a primitive 

 human being draped in furs. 



Many insects have highly developed social systems 

 which, superficially at least, seem much like those of 

 man. Such social systems are to be seen among the 

 ants, wasps, bees and termites. Some of these social 

 insects seem to be able to exchange a considerable 

 range of information, though on principles which are 

 quite different from those of articulate human speech. 



Some social ants make use of slaves, just as man used 

 to do — and still does in some places. Many make use 



[8] 



