ANIMAL BEHAVIOR, WITH EXAMPLES 



183 



it on the ground. When exam- 

 ining more closely into the cause 

 of this insect carnage, I have 

 been utterly taken by surprise on 

 lifting one of these insects to find it 

 in the grasp of an almost invisible, yel- 

 lowish white spider. I had passed the dead 

 insects on the flowers many times before I had seen the spider. 

 What wonder is it, then, that I had not seen her before. 



She has elongated front legs, and a peculiar inclination to 

 walk sideways or backwards with equal facility, and through 

 this resemblance to a crab's gait she is sometimes called the 

 crab-spider, Misumena vatia. Having become familiar with 

 her appearance, her attainments are more readily understood. 

 In the early part of September, one was detected in a flower of 

 the evening primrose, in the attitude ready to seize her prey. 

 Her appearance was of such a curious character that I have 

 endeavored to depict her in my drawings. Here she rested 

 with her small, atrophied, third pair of legs touching the stamen- 

 cross on each side, while the first and second pairs of legs were 

 widely spread apart, ready for instant action when the time came. 

 I watched her at intervals, but saw only an occasional insect 

 flying in the vicinity, as the flower did not happen to be in the 

 most favorable location. She stayed here at her station all 

 night and into the next day without capturing a victim. 



When the bright sunlight came out and the blossoms began 

 to fade, she changed her position, as shown in the left flower of 

 the second illustration. It was interesting to see her hanging 

 her legs out over the edge of the petals. Later, I saw her 

 slyly walk out of the now fast-wilting flower. Then she climbed 



