446 



LAUGHTON 



[chap. 18 



Fig. 12. 29° 17'N, 57° 23'W. Depth 5618 m. Abyssal hills southeast of Bermuda Rise. 

 Area of picture 2 by 2^ m. (Photo by L.G.O.) 



Rovmd manganese nodules each capped with a thin covering of sediment. The 

 scour pits around each nodule suggest currents which must have ceased before the 

 sediment cap was laid down. Note the shark's tooth in lower right and meandering ti-ack. 



Fig. 13. 32° 34'N, 117° 47'W. Depth 256 m. Slopes of Thirty-Mile Bank. Area of picture 

 H by 1| m. (U.S. Navy Electronics Laboratory photo by C. J. Shipek.) 



Angular nodules of phosphorite half buried in sediment and richly coated with 

 sponges, bryozoans and brachiopods. Note lobster-like crustaceans [Galathea cali- 

 forniensis) and starfish. 



