370 DWIGHT E. MINNICH 



others display little or no such tendency, while still others vary 

 widely in their deflections from time to time. Since the animal 

 moves in a uniform environment, the conspicuous asymmetry 

 of response so frequently noted must be attributed to internal 

 factors. Such factors are, for the most part, probably quite in- 

 dependent of hght. A more detailed discussion of these will be 

 presented in a subsequent section of this paper. 



4. Total darkness 



If internal factors are responsible for the asymmetric responses 

 of bees in non-directive illumination, a similar behavior should 

 be exhibited in the total absence of photic stimulation. Such 

 was indeed the case. Animals creeping on smoked paper, in 

 total darkness, showed the same conspicuous tendencies to loop 

 and turn as did animals in non-directive light (fig. 16). The 

 data here referred to were taken in connection with experiments 

 conducted for a different purpose. They are, therefore, not 

 sufficiently extensive to establish more than a similarity to the 

 behavior exhibited in non-directive light. 



Responses essentially like those of bees in total darkness have 

 also been described by Pouchet ('72) for the larvae of Lucilia 

 caesar, Davenport ('97) for the amoeba, and Frandsen ('01) for 

 the garden slug Limax. Frandsen' s observations in particular 

 bear a striking resemblance to those which I have just described 

 for the honey-bee in non-directive light. Thus he found that 

 while most of his animals looped in a fairly constant fashion to 

 the right or left, a few were extremely variable, while still a few 

 others moved in rather straight courses. The responses of creep- 

 ing bees in the total absence of photic stimulation are, therefore, 

 very similar to those observed for other animals under the same 

 conditions. 



6. Summary 



In the preceding pages certain responses of normal bees have 

 been described in considerable detail, but only as a prerequisite 

 to an adequate understanding of the behavior of the animals 



