250 
Peckham—The Sense of Sight in Spiders. 
other variety, would have succeeded in mating with her if they 
had not been separated. All continued to dance before her un¬ 
til at the end of fifteen minutes she was taken out, and painted 
with water colors, all over her abdomen, a bright blue, the nat¬ 
ural color being pale with reddish bands. After the paint had 
dried thoroughly she was put back into the box. The three 
light co lored males now treated her with complete indifference, 
passing close to her without paying her the slightest attention, 
exactly as though she belonged to another species. The niger 
showed some curiosity, keeping near her and watching her, but 
did not dance. After twenty minutes he suddenly leaped upon 
her, but was taken off. He then left her and did not renew his 
attentions. A second female was now put in. All four of the 
males at once began to dance excitedly before her and continued 
their display without pausing, for fifteen minutes when she was 
removed. All this time they had paid no attention to the blue 
female, but now they began to notice her a little, not dancing 
at all but sometimes pausing to look at her when they came 
near. They were left together for half an hour longer with no 
further results. 
In the next experiment we used entirely different spiders, 
though of the same species. A female was put in with four 
males, one of them being a niger. All became excited and at 
once began to dance. At the end of five minutes she was taken 
out and painted blue, as before. When dry, she was replaced. 
None of the males paid any attention to her for the first ten 
minutes, but after that one of the light colored ones gradually 
became excited, and ended by dancing before her in the most 
eager manner possible. The other males remained indifferent. 
This experiment was repeated with a fresh lot of spiders 
with the same results at first; but after the painted female had 
been in with the males for thireen minutes first one, then a 
second, and then a third of the light colored males danced be¬ 
fore her. 
At another time we put a female vittata into a box with six 
males, two of which were of the niger variety. Within a min¬ 
ute all but one (a light colored one) were dancing and postur¬ 
ing before her. We took her out, and painted her cephalothorax 
