RANGE OF VISION IN SOME ARANEIDA, 659 
of interesting experiments, which appear to fully prove the correct- 
ness of the authors’ (Dr. and Mrs. Peckham) conclusion that the 
spiders only recognise their lost cocoons by the sense of touch. 
Several Citigrade spiders were experimented with, but one or two 
references will suffice. The cocoon was taken from a female of 
Pirata minutus, and “no matter how anxious she was to find her 
eggs, and no matter how close they were brought to her, she 
never recognised them except by touch.’* For the next experi- 
ment, the cocoon of Pirata montanus was suspended at the end 
of a thread: “As the spider searched anxiously about, it was 
lowered until she could barely pass beneath without touching it. 
This arrangement required some manipulation, but we finally 
succeeded in suspending several cocoons at exactly the right 
height, and then watched the spiders as they passed and repassed 
without observing them. If, however, we allowed the cocoon to 
graze one of the posterior legs, the spider instantly turned and 
seized it. The position of the eyes of these spiders is such that 
unless they are totally blind they must have seen these suspended 
cocoons ; but they are as dependent upon touch for recognising 
their eggs as thoroughbred bloodhounds are upon the sense of 
smell when hunting their game, or as English greyhounds upon 
sight.” + 
As far as my experience goes, I certainly agree with Peckham. 
Lycosa godeffrow, L. Koch, and L. tristicula, L. Koch, when separ- 
ated from their cocoons, never recognised them until they hap- 
pened to touch them, and then they were eagerly seized, so that it 
would appear from these tests that Plateau and Forel formed a 
hasty conclusion when they said that the difficulty in finding their 
lost cocoons was evidence that the sight of the Citigrade was “ very 
poor and short.” But if further evidence were needed, it is only 
necessary to point out that in two instances the cocoons of Lycosa 
godefiroyi, after being taken from the spider, were tinted a pale 
green and replaced in the experimenting-box. This fact alone 
would, one would think, be sufficient to deceive them—that is, if 
they depended upon the sense of sight to discover their lost trea- 
sures ; but, nevertheless, directly one of the spiders touched its 
cocoon the latter was instantly seized. 
It is only reasonable to assume that spiders, dependent upon 
dexterity and cunning for the capture of prey, must be endowed 
with a long range of vision ; and this has been abundantly proved 
by Dr. and Mrs. Peckham in their extensive experiments with the 
Attide. These spiders, as Peckham says, lend themselves, by 
their natural habits, to more successful treatment under experi- 
ment than any other group, because, “when shut into a box which 
is supplied with light and air, they seem entirely unconscious of 
* Loe. cit., p. 237. + Loe. cit., p. 237. 
