PHOTIC REACTIONS OF TADPOLES 



271 



and the average of these two was considered to represent the 

 true value. Ahnost without exception, the second reading 

 taken agreed well with the previous uniform results. Five 

 experiments were made, a summary of which is given in table 

 8. In addition to this, the data are represented graphically in 

 figure 9, the reaction-time being plotted as a function of time 



TABLE 8 



Summary table of average reaction-times in seconds for tadpoles of Rana clamitans 

 in the process of fatigue. Light intensity, 10 candle-meters 



me m lii^ht- f^mutes 



Fig. 9 Curve illustrating the course of the process of fatigue. The reaction- 

 time, in seconds, is plotted as function of time in the light, in minutes. 



