172 INSECT BEHAVIOR 



Hundreds of species are known in the world and they are perhaps 

 one of the commonest creatures occurring in the United States. 



The female oniscus carries her eggs in a pouch which covers the 

 under surface of her thorax. The young are exactly like the adults 

 except for the last pair of legs, which are lacking, and these are not 

 acquired until later in life. The significance of this strange fact 

 would be hard to discover, and like the life histories of so many of 

 our tiny creatures, lies shrouded in mystery. 



It is strange that these creatures and the Aptera, still progressing 

 in our world today, have survived great upheavals of the earth, great 

 changes of climate, great floods and glacial periods, and yet have 

 come through unscathed to this modern century. Where great 

 mammals, birds and reptiles of bygone ages failed and left us only 

 fossil records of their existence, these tiny things succeeded and came, 

 living into our day. They have been handed down to us by Nature 

 as priceless heirlooms of our planet's ancient family. 



