82 THE OCEAN FLOOR 



would be ths sediment carpet coating the slopes of 

 mountains and surfaces of valleys. From the blueish 

 clay lining the continental slope, down which we would 

 make our entry into the abyssal region, we would come 

 to whitish or yellowish calcareous ooze spread over the 

 medium depths. Examining it through a magnifying 

 glass, we would find it consists of myriads of small 

 rounded-off tests or shells of dead plankton from the 

 surface of the sea — the Foraminifera which pullulate 

 especially in the tropical regions of our present oceans 

 and which for untold millions of years have been settling 

 to that great churchyard of marine creatures, the ocean 

 floor. In certain regions, especially in high southern 

 latitudes, a look through the microscope would reveal 

 the presence of tiny silica skeletons from marine algae 

 which thrive in the nearly ice-cold arctic and antarctic 

 water, forming a siliceous deposit of diatom ooze on 

 the bottom. Around the Scandinavian coasts their 

 annual flowering in early spring fills the larder of the sea 

 with materialized sunshine, transformed into potential 

 foodstuff in the form of this microscopic grass on the 

 meadows of the sea (Figure 29) . 



Proceeding to still greater depths, we would find the 

 hue of the sediment carpet changing to red or deep 

 chocolate brown. We would then have reached the 

 very basement of our planet, covered with the mysterious 

 red clay which carpets over 40 million square miles of 

 the deepest ocean floor. From it the tiny calcareous 

 shells would have mysteriously disappeared or else have 



