XIV SENSES—INTELLIGENCE ae 
exceedingly strange that the nomadic and hunting spiders, to 
which the sense of hearing might be expected to be extremely 
useful, should be deficient in this faculty, while the sedentary 
spiders, to which it would appear comparatively unimportant, 
should possess it in a tolerably developed form. That writer may 
possibly be correct in supposing that the sense, as possessed by 
spiders, is hardly differentiated from that of ordinary touch, and 
that the web-making species are only aware of sounds by the 
vibrations communicated to their feet by the medium of the 
web. However this may be, we must reluctantly but sternly 
reject the numerous and seemingly authentic stories, often con- 
nected with historic personages, which credit the spider with a 
cultivated taste for music. 
We have seen that among the spiders which possess a stridu- 
lating apparatus it is confined, in certain groups, to the male, or 
if present in the female it exists only in a rudimentary form. 
If in these cases stridulation has been rightly interpreted as a 
sexual call, the power of hearing, at least in the female, is of 
course connoted. The spiders in question are members of the 
Theridiidae, a family closely allied to the Epeiridae, and therefore 
more likely than most groups to possess the power of hearing. 
Theraphosid spiders show no response to the stimulus of 
sound, and among them stridulation is not confined to one sex. 
If, as is generally believed, the organ is used to warn off enemies, 
it is not necessary that the sound produced should be audible to 
the spider itself. If there be anv true hearing organ in spiders 
its location is quite uncertain. Some have supposed the so-called 
lyriform organs in the legs to have an auditory function, while 
others have supposed the power of hearing to reside in certain 
hairs, of which there are several different types distributed over 
the body and hinbs of the animal. 
Spider Intelligence.—The experiments performed by the 
Peckhams clearly proved that spiders have short memories—a 
sure indication of a low state of intelligence. Members of the 
Lycosid or “ Wolf-spider” group, when deprived of their cocoons, 
recognised them again after a few hours, but in most instances 
they refused to resume them after a lapse of twenty-four hours, 
and in every case an absence of two days sufficed to prevent any 
sign of recognition on their restoration. Moreover, when, after a 
shorter interval, the cocoons of other spiders, even of different 
