28 SPIDERS [CH. 



consequences follow? It will perhaps be most in- 

 structive to give in a condensed form the results 

 of an actual experiment selected from many per- 

 formed by two American arachnologists, George and 

 Elizabeth Peckham, whose researches have thrown 

 more light than any others upon the mental equip- 

 ment of spiders. They had an individual of the 

 small Epeirid species Cyclosa conica under obser- 

 vation for a month, and tested it almost daily 

 with the tuning-fork. At the sound of the fork the 

 spider would drop ; when it had recovered itself and 

 returned to the snare the fork would be sounded again, 

 and so on. Now on July 20 the spider fell nine times 

 successively the last three times only an inch or 

 two and then took no further notice of the vibrating 

 fork. On subsequent days, until August 5, she fell 

 either five, six or seven times, except on two occasions 

 when a day's test had been omitted, and then eleven 



*/ 



successive falls occurred before the spider ceased to 

 respond. On August 5 she seemed startled at the 

 sound but did not fall, though the fork was sounded 

 nine times. During the remainder of the experiment 

 she generally remained perfectly indifferent to the 

 fork, though on one or two occasions she partially 

 forgot her lesson and dropped a very short distance, 

 immediately recovering herself. 



Observe that the basis of educability is memory. 

 For a fortnight, in the case of this particular spider, 



