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A. IZUKA. 



net," two hand-nets and such other utensils as might be required for observ- 

 ing, capturing and preserving the worms. About eleven in the night, the 

 place was reached. More than half an hour was spent in the task of 

 preparing for the worm-fishing. Three more boats assembled at the 

 station, thus making a party of four boats each with a lighted lantern and 

 a " pyramidal net " planted on the bottom. The four nets were so set 

 that their mouths lay almost in a streight line. About a quarter past 

 twelve (0.15 a.m. 17th, Dec.) I have observed the first swimming worms. 

 About fifteen minutes later, the worms had become so numerous that I 

 could scoop up a number at a time with the hand. The swarm was 

 thickest after about three quarters of an hour from the beginning. All the 

 worms swam about rapidly, somewhat after the manner of eels, darting in 

 all directions. It then almost appeared that the worms in a sheet had 

 covered up the surface of the water. I ascertained that the swarm 

 reached to a depth of five or six feet from the surface. About an hour 

 and a half from the beginning, the worms began to gradually disappear, 

 and after about half an hour (at 2.15 a.m. Dec. 17., about two hours after 

 the beginning of the swarming), there was no longer a single worm found 

 swimming. The work was now over, but the boats stuck to the bottom 

 on account of the low-water and had to await the return of flood in order 

 to be able to move off. At about nine o'clock in the morning of the 17th, 

 all the boats were at home again. Some of them had alone captured over 

 160 tabfuls* of the worms. The entire catch on that night at the six 

 stations, was estimated at no less than 2,620 tabfuls. 



The above account, except so far as concerns the hours of day, may 

 in general be considered to hold good for all the occasions when the 

 swarming takes place in large numbers. It seems certain that a large part 

 of the swarms is carried off into the sea by the ebbing tide. 



The results of my observations on the swarming in the year 1906 

 may be tabulated as follows : 



* A tabful equals in volume to about 17 liters. 



