2 tunnyo This decrease in the number of fish would, of course, 

 decrease the absolute values of the quantitative data^ particularly 

 the counts,, but it would not necessarily change the difference between 

 control and test datao Apparently 13 fish gave d much greater 

 response than 2 fish to the seume amount of materialj, suggesting a 

 "group" effect- "=a contagious excitemento On the other hand, the 

 decrease in response may have been related to decrease in the 

 "condition" of the fish and a declining interest in food substances 

 during the winter monthSo 



SOURCE AND PREPARATION OF TEST SUBSTANCES 



Materials 



The materials which were used are listed for each 

 experiment in the appendix at the end of this reporto 



Because of its ready availajjility and also because it had 

 given a positive response in experiments conducted by v^n Weel 

 (19521, most of the preparations consisted of extracts of tuna flesh, 

 including skipjack, tunnyj yellowfin, and bigeyCo In addition, ex- 

 tracts of trina skin, blood, liver, ovaries, testes, and unsegregated 

 viscera were usedo 



A few tests were conducted with extracts prepared from 

 "white ■= fleshed" fish (as opposed to the red«fleshed tunas) when 

 materials were available. They included "aholehole" (Kuhlia 

 sandvicensis) flesh, jack ( Caranx l flesh and blood, barracuda 

 ^§£^Y£££B^ .^!l£j^^£H^ J -l^s^o ^nd wahoo ( Acanth ocybiurn s^lgj;^dri ) 

 fleslio 



The tuna and other fish used in these preparations were 

 either fresh-caught or fresh -frozeno They were obtained from our 

 own fishing operations, from the Pacific Oceanic Fishery 

 Investigations, or from the Hawaiian Ttrna Packers, Ltdo 



Beef blood obtained from a local slaughter house was 

 used in comparison with fish bloodo 



Tuna cannery byproducts, including fish meal, stick- 

 water (effluent), and various preserved digests of skipjack viscera 

 made for other purposes by Mr, F^ Jermann oi Hdwaiian Tuna 

 Packers, Ltdo , were testedo A herring reduction pl^ant byproduct, 

 "condensed herring solubles" prepared by Bo Co Packers, Ltdo , 

 Vancouver- Canada^ was also usedo 



27 



