282 
PecJcham—The Sense of Sight in Spiders. 
then almost impossible for the fly to effect an escape. But if, 
before the spider gets to it, the fly takes wing, and fixes upon 
another place, it whirls nimbly about, and still keeps its eyes 
upon it, in order to commence a fresh attack.” 5 
It is not probable that a spider could see a fly at a distance 
of three or four yards, but Bingley could scarcely have spoken 
in this way if he had not been sure that it could see to a 
considerable distance. 
In 1886 Forel published a paper on the sensations of insects. 
It is his conclusion that the sense of sight in spiders is so bad 
that if the flies were not so stupid and so imprudent they would 
never be caught. He says that the jumping spiders miss fifty 
flies to one that they catch. 6 This author, however, speaks of 
his experiments in such a general way, giving no details, that 
they are of but little value in the solution of the problem. It 
is rash to draw positive conclusions from superficial observa¬ 
tions. To an ordinary observer nothing could seem more sense¬ 
less than the way in which ants run about on the ground. Even 
after an ant has found some choice morsel which it wishes to 
carry to the nest, it runs now this way and now that in what 
appears to be a perfectly aimless manner; and yet if a person 
has the patience to follow one of them through all its wander¬ 
ings it will be seen to reach the nest at last. Another animal 
which might easily be misunderstood is a fish that inhabits our 
inland lakes (Coregonus artedi, var. sisco) that during a very 
short season of the year will bite at almost anything. After 
that time they may have their favorite fly dangled all around 
them and yet not take it under any circumstances, appearing 
perfectly blind. 
To discover the limits of the special senses of an insect is a 
very difficult matter. Only a prolonged study of its life his¬ 
tory, pursued through several years and during different 
seasons, on a number of different species and on many individ¬ 
uals of both sexes, is likely to lead to important conclusions; 
and in reporting their experiments all writers should remember 
Lange’s words on the subject of scientific observations: “An 
6 Animal Biography, Vol. Ill, p. 455. 
6 Sensations des Insectes, premiere partie, Recueil Zoologique Suisse, 
T. IV, No. 1, p. 41. 
