470 ALFRED O. GROSS 



on a trough containing these animals the majority of them col- 

 lected in the green and yellow, the most luminous region of the 

 spectrum as judged by our eyes. From the results of these 

 experiments Bert concluded that the vision of the lower organ- 

 isms is the same as it is of the eye of the normal human being. 

 Merejkowsky ('81) experimented with spectral colors upon 

 Balanus larvae and the marine copepod Dias longiremus. He 

 recognized the importance of the intensity of the light and 

 attempted to eUminate this factor by equaUzing the luminosity 

 of the respective colors as judged by his own eye. Under these 

 conditions Merejkowsky found the animals distributed equally 

 in the different colors. He opposes the view of Bert concerning 

 the vision of the lower animals and concluded that the lower 

 crustaceans cannot see the different colors and are conscious of 

 only one color in variations of intensity. ^'Nous percevons les 

 couleurs comme couleurs, ils ne les pergoivent que comme lumiere" 

 ('81, p. 1161). 



Lubbock ('79, '81 a) tested the reaction of ants with lights 

 produced by means of colored glass placed over different parts 

 of artificial nests. From his numerous and ingenious experi- 

 ments he concludes that ants have the power of distinguishing 

 color, that they are very sensitive to the violet and that their 

 perception of color is very different from ours. In two papers 

 published in 1881 and 1883 he describes experiments made with 

 spectral light upon Daphnia pulex. His results are in agreement 

 with those obtained by Bert except that he found the Daphnia 

 to be responsive to the ultra violet — a fact denied by Bert. In 

 a more recent publication ('04) are described an extensive series 

 of experiments upon bees made in the field. Lubbock placed 

 drops of honey on pieces of colored paper and glass and observed 

 the bees which visited the different colors. The results of his 

 investigations, he thinks, prove that bees can distinguish colors 

 and that they exhibit a decided 'preference' for the blue. Lub- 

 bock's view, that insects can perceive the different colors, is in 

 general agreement with the results of the work by Forel ('88, '01, 

 '04) on ants and bees; the Peckhams ('87, '94) on wasps and 



