154 DOMESTICATED TROUT. 



denly, with a singular and irresistible instinct to hide 

 under something. If they do not find anything in the 

 troughs to get beneath, they all try to hide under each 

 other. 



From this moment they are never at rest day nor 

 night, but, gathering together in large bodies, will seek 

 some dark corner, and pass their whole existence in 

 one incessant and ineffectual struggle to get under 

 each other and out of sight. In this struggle they 

 crowd together in swarms, like bees. I have often seen 

 a solid writhing mass of them, over half an inch deep, 

 which could almost be covered with the hand, and 

 which could not have numbered less than ten thou- 

 sand.* 



This instinct to hide is so strong that they will 

 dive head first, with all their might, into the gravel, 

 and insinuate themselves into holes and chinks where 

 you would think it impossible for anything to get, 

 and where sometimes they can never get out again. 

 Then woe to the little creatures if there are chinks 



Seventh day. Bodies acquiring decidedly more solidity. Sac 

 more pointed. 



Eighth day. Fish decidedly harder, darker, and firmer fleshed. 

 The herding-together instinct shows itself for the first time to- 

 day. 



* It has been thought by some that this crowding together is 

 hurtful, but I never knew a single fish to be injured by it, though 

 I have sometimes turned more than twenty thousand in together 

 at this stage. Contrary to some authorities, I keep the alevins 

 in shallow water and a strong ripple. If they were in deep water 

 with a slow current, I think there might be danger of injury from 

 excessive crowding. 



