CALIFORNIA FISH AND GAME. 103 



held in a separate trough. Control fish were obtained by dipping out 

 a few fish with a net and counting out fifty or so without conscious 

 selection. Great care was used in this respect so that the control would 

 l>e exactly representative of the size classes of marked fish in order that 

 the control might be used for possible future study. The control 

 remained two months in the hatchery troughs from the time of marking 

 until the middle of January, 1920. The control fish were then bottled 

 in formalin and shipped to Professor J. 0. Snyder of Stanford Univer- 

 sity, being received by him January 19, 1920. Through an oversight 

 when bottling the control at the hatchery, the fish marked by Phillips 

 and those marked by Scofield were not kept separate, but since the 

 percentage of regeneration has been found to be almost negligible this 

 attempt to determine the regeneration percentage for each person's 

 marking was scarcely necessary. Roughly, 100 of the control marked 

 by Scofield were shipped to Professor Snyder for his study very soon 

 after the marking and received by him December 1, 1919. Of the 

 25,850 fish marked 850, or roughly 3 per cent of the total were retained 

 as control, thus leaving an even 25,000 marked fish to be liberated. 



Percentage of Fin Regeneration. 



To determine the percentage of fins which might be expected to 

 regenerate, the control was examined by W. L. Scofield in February, 

 1920, with the help of Professor Snyder and Mr. Willis Rich of the 

 United States Bureau of Fisheries. Of the 573 specimens examined 

 but 8 or 1.4 per cent showed signs of possible regeneration and in sev- 

 eral of these cases the resulting ventral fin would probably be so 

 deformed as to be recognizable as a mark when found with a missing 

 adipose fin. In no case had the adipose fin shown any sign of 

 regenerating. 



Injury from Marking. 



But one death was noted among the marked fish soon after marking 

 and none among the control from November 3 to 15, 1919. A report in 

 December from the hatchery stated that the control was apparently 

 perfectly normal and healthy with very few deaths. A few fish were 

 stunned by the rough handling while being marked but when returned 

 to the water would swim off after about one minute and show no 

 further signs of discomfort. 



Summary. 



Of 1,153,000 king salmon eggs taken in November, 1918, from Mill 

 Creek of the Sacramento, and hatched at Fall Creek Hatchery on the 

 Klamath River in February, 1919, 903,000 were liberated in the Klamath 

 about July 1, 1919, and 250,000 were held in a rearing pond. In 

 November, 1919, the 250,000 from the rearing pond were liberated in 

 the Klamath River after 25,000 of them had been marked by removing 

 adipose and right ventral fins. 



