1896.] Zoology. 673 
following description of one of the many experiments described in the 
article serves to show the method of investigation: 
A male of Saitis pulex was put into a box containing a female of the 
same species. “The female was standing perfectly motionless, twelve 
inches away, and three aud a half inches higher than the male. He 
perceived her at once, lifting his head with an elert and excited ex- 
pression, and went bounding toward her. This he would not have 
done if he had not recognized her as a spider of his own species. 
When four and one-half inches from her he began the regular display 
of this species, which consists of a pecular dance. This he would not 
have done had he not recognized her sex.” 
At another time a male of Hasarius hoyi was dropped into a box 
with another male which was standing seven inches away. “He at 
once threw up his first legs, this being a challenge to battle. The other 
male responded by throwing up his first legs. The two advanced upon 
each other slowly, and when only two inches apart began to circle 
about each other, waving their legs. The same male when put into a 
box with a female saw her as she stood quite eleven inches away, and 
at once lifted his first legs, not straight up, as in the case with the 
other male, but obliquely, and began to move with a gliding gait from 
side to side, this being the characteristic display before the females in 
this species.” 
That the spiders recognize each other by sight and not by any other 
sense is evidently shown by the fact that they remain unconscious of 
each other’s presence when back to back, no matter how excitable they 
are when they come within range of each other’s vision. As a further 
evidence of recognition by sight a male of Dendryphantes elegans was 
removed from the box in the midst of his courtship of a female, his 
eyes gently blinded with paraffine, and then restored to the box. He 
remained entirely indifferent to the presence of the charmer that had 
so much excited him a few moments before. 
To sum up the result of these experiments: 
“The Attidæ see their prey (which consists of small insects) when 
it is motionless, at the distance of five inches; they see insects in mo- 
tion at much greater distances ; they see each other distinetly up to at 
least twelve inches. The observations on blinded spiders, and the 
numerous instances in which spiders were close together, and yet out 
of sight of each other, showing that they were unconscious of each 
other’s presence, render any other explanation of their action unsatis- 
factory. Sight guides them, not smell.” 
