156 THE OCEAN FLOOR 



jaws, somewhat resembling those of snakes. Obviously 

 their chances of getting a square meal from the sparse 

 bottom fauna are so rare that each occasion has to be 

 utilized to the full. Cases are known of a fish from a 

 great depth which when discovered had recently swal- 

 lowed another fish considerably bigger than itself 

 (Figure 47). The whole problem of the nutrition of 



Fig. 47. Deep-sea fish after a square meal 



abyssal fauna presents interesting aspects and raises 

 many questions which will have to be answered by 

 future deep-sea expeditions. 



Trawling in Great Depths 



The most efficient gear for collecting animals from 

 very great depths is the trawl, a wide-open sack of 



