PHOTIC KEACTIONS OF HONEY-BEE 



379 



Some of the more vigorous animals survived not only a third day 

 of experimentation, but lived on for three or four days, and in a 

 few instances even longer. Although no further trials were made 

 with such bees, they were kept and, as far as possible, records of 

 their subsequent longevity taken. 



Having described the first type of non-directive light experi- 

 ment in considerable detail, the second type may be described 

 very briefly. It differed from the first only in the method of 

 making pairs of determinations. In this case, the two determi- 

 nations of a pair were made during the same period of time, 



instead of an appreciable interval apart. The bee was first tested 

 in one intensity of light, then within a minute or so in the other 

 intensity, then again in the first, and so on until a series of one to 

 five records had been completed for each intensity. Care was 

 exercised, however, even with this rapid alternation of intensi- 

 ties, always to expose the animal for thirty to sixty seconds in a 

 given intensity before subjecting it to a trial in the same. The 

 following protocol from bee no. 83 (table 4) will illustrate this 

 method of making determinations. 



In both types of experiment, there were obtained for each bee 

 a number of pairs of determinations, usually four to ten, depend- 

 ing upon the longevity of the individual. The records of each 



