CHAP. VI. 



DEEP-SKA DREDOTNG. 



2.5 7 



derms, corals, and sponges, on the contrary, are bulky 

 objects, and are frequently partially buried in the 



" ^ up .. 



Fir,. 51.— Dredge with * hempen tangles ' 



mud or more or less firmly attached, so that the 

 dredge generally misses them. With the tangles it 



s 



