THE SCHOOLS OF LITTLE ARROWS 



The young of Siiversides have their fling at sea, 

 drifting about on the surface after hatching, far off 

 shore. I have taken them in surface hauls as far out 

 as three miles, but singly, with no hint of gregari- 

 ousness. 



The nocturnal dissolving of a school is a very 

 delicately balanced phenomenon. Twice I have been 

 watching schools of small fry on a hot, sunny day 

 when a dark thunder cloud suddenly obscured the 

 sky. Automatically, as if they were chemical mole- 

 cules acted upon by some powerful reagent, the 

 mass loosened, a few even frayed out, six in one 

 group began snapping at some prey invisible to me. 

 On the first occasion the rain began to come down 

 in sheets and completely blotted out my submarine 

 view. The second time, the storm did not material- 

 ise, the sun reappeared and the strayed atoms gath- 

 ered close once more. With sundown comes the 

 slackening of this schooling instinct and when I 

 light a submarine light, the Siiversides come casu- 

 ally, in ones or twos. Feeding probably goes on at 

 night, as during the day, for hour after hour, not 

 the slightest attempt is made by the thousands to 

 capture food. 



Bermuda fishermen tell how these little fish keep 

 together for a week or two after the mackerel ar- 

 rive, and it is then that we can see the two kinds 

 of gregarious fish in full action — the one pursu- 

 ing, the other fleeing — each to the limit of its 

 power. But before long terror of their voracious 

 enemies becomes so great that the Siiversides 



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