THE SENSES AND THEIR ORGANS. 305 



should be found to possess hearing in a degree of acuteness. It is not 

 often that one finds a contradiction like this in natural history, viz., that 

 those animals that most need a certain organism or sense have none, while 

 those which are in least need are highly sensitive. 



The experiments of Mr. C. V. Boys l would really lead to the same 

 conclusion. He notes that after a spider has been dropped from its web 



by bringing a tuning fork near it, if the fork is made to touch 

 Mr. Boys' an y p ar ^ Q f ^he we ]- ) ^ e spider j s aware of the fact, and climbs 



the thread and reaches the fork with marvelous rapidity. Mr. 



Pcckham observes and records a similar fact in the case of Epeira 

 strix and Epeira labyrinth ea. 2 How shall we account for these actions? It 

 appears to me clear that when the fork was placed near the animal its vi- 

 brations agitated the hairs upon the body and the spinningwork immediately 

 under and around, just as a large insect hovering near in the same posi- 

 tion would have done. The spider, therefore, did in the case of the tun- 

 ing fork what it would almost certainly have done in the case of the in- 

 sect it dropped from its hub as a measure of defense. 



In fact, a spider seated upon its hub is ordinarily at a decided disad- 

 vantage when an insect enemy, such as a wasp, approaches near it. Its 

 best defense, therefore, is to get out of the way. But it is quite a differ- 

 ent thing when its enemy appears at any viscid part of the web and by 

 the agitation thereof gives indications that it is captured. This is a signal 

 which the spider understands to mean, in almost every case, that its vic- 

 tim is ensnared and it can approach it with comparative safety. For this 

 reason the spider that would run from an insect or a supposed insect that 

 seemed to threaten it, would run towards the same when it appeared to be 

 captured and harmless. In these experiments, therefore, I see simply dif- 

 ferent manifestations of the same sensation of touch under different excit- 

 ing causes. 



VIII. 



In connection with these observations upon the auditory powers of spi- 

 ders, one must at least glance at the numerous stories about, and prevalent 

 beliefs in, the sensitiveness of spiders to music. There is such a 

 discrepancy between belief in this commendable trait and the 

 t M ' general contempt and disfavor with which araneads are regarded, 

 that one might incline to think there is good grounds for the 

 tradition, since it would hardly have arisen under the circumstances with- 

 out some basis of truth. Certain it is, the opinion is quite ancient and is 

 widely distributed. Nor are there lacking incidents of seeming historic 

 verity to be cited in confirmation thereof. It may be of value, it will at 

 least be interesting, to quote a few of these. 



'Nature," XXIII., pages 141), 150. - Op. cit., page 411. 



