384 DWIGHT E. MINNICH 



the functional eye, which was always much more pronounced in 

 the intense than in the weak illumination. In other words, these 

 individuals always yielded positive values of d of rather high mag- 

 nitude. Bees nos. 73, 83, 95, 105, and to a lesser extent numer- 

 ous others afforded striking examples of such behavior. These 



24 mc. 



957 



Fig. 12 A pair of determinations of bee no. 42, left eye black, non-directive 

 light. The records are numbered in the order in which they were taken. 



animals were all thoroughly vigorous individuals, surviving not 

 only the three days of experimentation, but living on for at least 

 two days thereafter. Two of these bees, in fact, survived no less 

 than four days after the conclusion of the experiment. 



In figures 14 and 15 are shown pairs of determinations from 

 two of these animals. The eight records of bee no. 73 (fig. 14) 

 were taken in the course of 28-4 minutes, while the six records of 



