PERCEPTION OF COLOUR. 321 



I then removed the yellow paper and honey, and 

 placed the honey which had been on the green paper 

 about a foot from it on the table. 



At 8.15 she returned and lit on the green paper, 

 but immediately flew off to the honey. I then trans- 

 posed the honey and the paper. 



At 8.24 she returned and again lit on the paper, but 

 immediately flew off to the honey. 



Thus, therefore, though it is clear that wasps can 

 distinguish colours, they appear, as might be expected 

 from other considerations, to be less guided by them 

 than is the case with bees. 



I have been much struck by the industry of wasps. 

 They commence work early in the morning, and do not 

 leave off till dusk. I have several times watched a 

 wasp the whole day, and from morning to evening, if 

 not disturbed, they worked without any interval for rest 

 or refreshment. 



Being anxious to compare bees and wasps in this 

 respect, on August 6, 1882, I accustomed a wasp and 

 three bees to come to some honey put out for them on 

 two tables, one allotted to the wasp, the other to the 

 bees. The last bee came at 7.15 p.m. The wasp con- 

 tinued working regularly till 7.47, coming at intervals 

 of between six and seven minutes. Next morning, 

 when I went into my study a few minutes after 4 a.m., 

 I found the wasp already at the honey. The first bee 

 came at 5.45, the second at 6. 



The wasp occupied about a minute, or even less, in 



