190 DEEVEY 



Carboniferous, the early Triassic, and the early Tertiary periods. By comparison 

 with these "normal" times (normal with respect to 9 S), when most of the 

 interesting events seem to have taken place on land, the Ordovician period seems 

 to have had too much anaerobiosis and recycling, and the Permian and 

 Cretaceous too little. 



For a final comment on recycling, in language appropriate to the grandeur of 

 the process, I turn to Bidder. Nearly 50 years ago that great student of 

 sponges noticed how Euplectella, the Venus's flower basket, lies on the floor of 

 the deep ocean, athwart the North Atlantic Deep Water on its way to becoming 

 the Equatorial Divergence. "Food is brought to them," he said, and "waste is 

 taken away. For them in their eternal abyss, with its time-like stream, there is no 

 hurry, there is no return. Such an organism becomes a mere living screen 

 between the used half of the universe and the unused half — a moment of active 

 metabolism between the unknown future and the exhausted past." 



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