262 



BRADLEY M. PATTEN 



TABLE 4 



Reactions of Mastigopr actus to equal bilateral illumination. The opposed beams 

 were each of 120 candle meters intensity. Measurements are recorded in degrees 

 of deflection from an initial path of locomotion. In figure 3, C the same meas- 

 urements are plotted graphically 



The reaction measurements given in tables 1 to 4 have been 

 summarized graphically in figure 3. The circles represent the 

 observation circle of the apparatus. The direction of the light 

 rays is indicated by groups of arrows. At the center of the 

 circles are heavy arrows indicating the initial position of the 

 animal for each series of experiments. Each of the arrows indi- 

 cating the path taken by the animals in response to stimulation, 

 represents the average point of emergence and approximately 

 the average path for ten trials of one individual. 



The reaction measurements presented above, cover the deter- 

 minations which it was planned to make on normal animals. 

 The results of some of the preliminary experiments with partially 

 blinded animals seem to have a place here inasmuch as they 

 help to estabhsh the rehability of the normal reaction measure- 

 ments as a basis for future comparisons. Moreover, they are 

 significant in indicating the correctness of our hypothesis that 

 normal orientation depends on the lanaintenance of stimulation 



