COLOR IN PLANTS 159 



tion of nectar and odoriferous oils, and by the formation of a 

 surplus supply of pollen, plants invite the visits of insects, 

 and that they sometimes adopt remarkable means to secure 

 cross-fertilization by the aid of the visiting insects. Careful 

 experiments have been made by numerous competent 

 students to determine if color in itself is recognized by 

 insects of different sorts. These have established the fact 

 that color is recognized by insects of many kinds, and that 

 to certain species of insects different colors have different 

 degrees of attraction. Also it has been shown that the most 

 attractive color is not always the same for two species of 

 insects. 



Lord Avebury's experiments upon bees are worth our 

 attention for a moment, as an illustration of the methods 

 which have enabled us to draw these conclusions. In a 

 very brief summary of an extended series of experiments 

 Lord Avebury says : " I placed slips of glass with honey 

 on papers of various colours, accustoming different bees to 

 visit special colours, and when they made a few visits to 

 honey on paper of a particular colour, I found that if the 

 papers were transposed the bees followed the colour." 

 Describing another series of experiments, he says : " I took 

 slips of glass of the size generally used for the microscope, 

 viz. three inches by one, and pasted them on slips of paper 

 coloured respectively blue, green, orange, red, white, and 

 yellow. I then put them on a lawn, in a row, about a foot 

 apart, and on each put a second slip of glass with a drop of 

 honey. I also put with them a slip of plain glass with a 

 similar drop of honey. I had previously trained a marked 

 bee to come to the place for honey. My plan then was, 

 when the bee returned and had sipped for about a quarter of 



