PLATE 12 



Figs. A-F. — Station 24, canyon head, east wall, 250-280 fms. 



A-D, Silty mud (cloud produced by compass indicates mud content); small linear 

 depressions, particularly noticeable in B, produced by crabs. Crab in A is 

 Geryon quinquedens Smith. Another unindentified crab in D (arrow). Subcircular 

 depressions probably formed by benthic fish. Linear depressions of unknown 

 origin in B. Worm tubes (arrows) projecting from bottom in C. 



E&F, Bottom similar to above. Bottom-living flat fish (arrow in E) produce sub- 

 circular depressions in fine sediment. 



34 



