Nos. 455-456.] HEARING AND SMELL IN SPIDERS. 865 



responses were exactly the same as in the foregoing series 

 Thus it was shown that the sense of smell is not localized in 

 the palps nor in any one pair of legs, but that each is capable of 

 perceiving the stimulus to a certain degree and of giving a defi- 

 nite response to it. 



d. Observations on Individuals loith the Sense Hairs removed. 



The theory has several times been advanced that the long, 

 spiny hairs on the legs of these spiders are organs of special 

 senses, accordingly all these hairs were cut off the tarsi and 

 tibia of male No. 94 and after twenty-one hours it was tested 

 with lavender oil. Each leg responded as do those from 

 which no spines were removed. 



Female No. 95 had the hairs cut from the entire leg and each 

 leg sand-papered, still it gave the normal response to bergamot 

 twenty-one hours after the operation. 



Female No. 96 had all the legs sandpapered, yet after only 

 an hour's time it responded normally to bergamot, raising each 

 leg in succession. 



Male No. 97 had the tarsus of each leg removed and the 

 spider seemed to suffer more than when an entire leg was cut 

 off. However after twenty-two hours it responded normally to 

 bergamot, raising each leg as it was stimulated. It was not 

 considered safe to cut the legs- at any higher joint, but the 

 experiments seem to indicate that the entire leg possesses the 

 ability to perceive sensations of odors. 



3. Conclusions. 



1. Neither Geolycosa nor Pardosa respond to tuning torks 

 of 128, 256, 320, 384 and 512 vibrations. No responses 

 were given to a metal bar of approximately 2300 vibrations 

 nor to the crashing sound of a metal plate when struck with a 

 bar. Therefore it is quite probable that these spiders do not 

 hear at all. 



2. It might be supposed that possibly this extreme quiescence 

 was itself an indication that the spiders perceived the tones and 

 responded in this way; however the fact that these spiders 



