Collecting 1 1 



The tangle or mop. This implement (Fig. 13) may easily be made 

 by attaching long loose cotton strands to an iron bar. When trailed along 

 the bottom it captures echinoderms and spiny crustaceans with which it 

 may come in contact. The tangle is widely used in Long Island Sound 

 by the oystermen for removing starfish from their oyster bottoms and is 

 available in various sizes and styles. 



The grapple. The grapple (Fig. 14) consists of a number of steel 

 wires passed through a galvanized pipe about one foot long and 1% 



Fig. 13. — The tangle. 



Fig. 14. — The grapple. 



inches in diameter, the inside of which is filled with lead. The lower 

 ends of the wires are bent back to form hooks, the upper being twisted to 

 make a loop for the attachment of a line. The grapple is very useful 

 for collecting submerged vegetation which may contain rich fauna of 

 crustaceans, worms, Bryozoa, etc.* 



The plankton net. Small organisms suspended in the water are col- 

 lected by means of a plankton net (Fig. 15) which is towed behind the 

 boat or is allowed to sink and is then slowly hauled up. To avoid back- 

 washing of the material caught in the net the rate of towing or hauling 

 should not exceed 1 meter per second. Plankton nets may be made of 

 various grades of bolting silk depending upon the size of the organisms 

 one is planning to catch. For small planktonic forms No. 20 or 25 



♦Editor's Xote: Lacking a grapple, a substitute for it may be made by coiling a long 

 piece of barbed wire in a circle, fastening it at the overlaps, and attaching a weight 

 at one side and a throwline at the other. This will gather submerged vegetation effectively. 

 J. G. N. 



