150 NATURAL SCIENCE. March, 



The Courtship of the Spider. 



The antics of the male spider during courtship are well known, 

 largely owing to the careful observations of two American naturalists, 

 Mr. and Mrs. Peckham. There are, however, the most diverse ideas 

 as to the precise distance at which a spider can see a fly or a lady 

 spider. The extremes are one-eighth of an inch on the one hand, and 

 "three or four yards " on the other. These differences of opinion 

 require, if possible, some reconciliation. And Mr. and Mrs. Peckham 

 attempt this, partly by direct observation and partly by criticism. 

 M. Plateau, to whose experiments upon mimicry and colour-meaning 

 we referred in our last number, seems to have based his theory of 

 limited vision in spiders upon the futile attempts which a female wolf 

 spider makes to recover her egg-sac when it has been snatched away. 

 According to the Peckhams, this does not necessarily go for much 

 in the way of the desired proof. For the egg-sac is manufactured in 

 such a position that the anxious parent has probably never seen it 

 in her life, and only recognises it by touch. Direct experiment 

 tended to prove this assertion. There is, too, as an instance of 

 aggressive clearness of vision, the terrible spider of the pampas, 

 described by Mr. Hudson, which starts in pursuit of anyone passing 

 within three or four yards of its lurking place. Some little spiders kept 

 in captivity darted upon a gnat when it was five inches away. But the 

 sharpness of vision appears to be accentuated by love. A male of 

 Saitis pulcx was put into a box in which was a female of the same 

 species twelve inches away ; we are told " that he perceived her at 

 once, lifting his head with an alert and excited expression, and went 

 bounding towards her." That recognition, in these cases, really is 

 due to sight, and not to any other sense, appears to be shown by the 

 fact that if two spiders are back to back they do not become aware of 

 each other's presence, no matter how close they may be. Moreover, 

 one male, when in the ecstasy of courtship, was interrupted " by 

 taking him out and gently blinding his eyes with paraffin. He was 

 then restored to the box, where he remained quite indifferent to, the 

 presence of the females which had excited him so much a few 

 moments before." But one of these males, apparently suspecting 

 some trick, carefully cleansed his eyes from the paraffin by rubbing 

 them with the palpi, and then began " dancing before a female three 

 and one-half inches away." A female of a species named Astia vittata, 

 observed to attract the opposite sex, was temporarily removed and 

 painted of a bright blue ; the male spiders, who had before been 

 unremitting in their attentions, treated her with the most absolute 

 indifference. After a few moments, however, one of them suddenly 

 leapt upon her, but whether this was the result of hunger or of love 

 does not appear. At any rate, the experiment seemed to argue some 

 colour-sense in the creatures. A further series of experiments put 

 this belief upon a firmer footing. The approach to the lair of a 

 spider was covered with variously coloured paper, which at first 



