152 American Fisheries Society 



Expressed in a slightly different way, cooking the liver 

 adds 17V2 Per cent, to its cost. This increased cost is 

 much more than offset, however, by the gain in results of 

 from 48 to 200 per cent. 



II 



Factors Other Than Food That Influence the 

 Development of Salmon Alevins. 



Seven uncovered glass dishes, each 9 cm. in diameter, 

 were each supplied with 150 ccm. of spring water. On 

 January 3rd Chinook alvins, just hatched, were distrib- 

 uted among them as follows : Dish 1,3; dish 2, 5 ; dish 3, 

 10 ; dish 4, 15 ; dish 5, 20 ; dish 6, 25 ; dish 7, 30. All lived, 

 without change of water, until January 23rd, when all 

 the fish in dish 7 died. 



On January 24, all in dish 6 died, several of them hav- 

 ing begun to show clear signs of diminishing vitality by 

 January 16. 



On January 24, 3 individuals in dish 5 died, and the 

 others seemed so feeble that the water was changed. By 

 February 15, 19 had died, the rest two days later. 



On February 2, 14 of the 15 in dish 4 died, the last dy- 

 ing the next day. 



On February 1, the fish in dish 3 were observed to be 

 less lively than at first. On February 15, 8 died; on 

 February 17, the other two. 



Of the fishes in dishes 1 and 2, all lived until March 23, 

 when they were killed by a rise in temperature of the 

 water, the dishes having been exposed inadvertently to 

 the sun all day. Up to this time they had been active and 

 healthy. A growth of algae in the dishes led to a change 

 of water in both dishes on February 21. It is probable 

 that they would have lived indefinitely had they not been 

 subjected to the abnormal rise in temperature on 

 March 23. 



Notwithstanding their apparent health and nervous 

 activity, the individuals in dishes 1 and 2 were much 



