CHART I. 



Graphs of Reaction of Fish to Chloroform and Ether. 

 (See Table I.) 



BULLHEAD SUCKER BULLHEAD BULLHEAD 



Control 3 Expt. A. 6. Expt. B. I. Expt. B. 3. 



BULLHEAD 

 Expt. B. 10. 



CHART I. Reaction graphs. The drug was introduced at the right ; its concen- 

 tration is indicated by the larger black area in the heading. These graphs repre- 

 sent parts of experiments only and are meant to show, primarily, the type of action 

 of the fish to certain poison concentrations in the gradient tank. To the extreme 

 left is shown a control experiment on a bullhead and it should be compared with 

 the three to the right (of series B) in order to bring out the distinctive types of be- 

 havior involved. Not considering the sucker experiment and taking only those 

 shown on the bullhead it is plain that an intergradation of action can be traced 

 from the one on the extreme left to the one of the extreme right. 



The reaction of the sucker to chloroform is shown in the second graph to the 

 left and should be compared with the reaction of the bullhead to ether as shown in 

 Expt. B. i for the concentrations are approximately isotoxic; the bullhead showing 

 notches which are never present in the charts of suckers. 



