50 
NATURE S CRAFTSMEN 
remember, but for the clue of thread with which 
Ariadne supplied him. 
“ Do the processionaries return to the feeding- 
grounds of the night before? Hardly, since they 
cannot see, and the direction of their expedition is 
left entirely to the fickle vagaries of the groping 
wriggler at the head of the file. How does he 
manage to find pasture at all; can it be that he 
smells it? Fabre proved that this is not the 
case. A host of hungry caterpillars from his 
insectary passed close beside a pine branch, after 
long hours of fasting, without betraying any ea¬ 
gerness or showing even a desire to stop. No, 
they recognize food only by touch. So long as 
their lips do not actually brush against the pas¬ 
ture, they will proceed on in their wavy line. 
“Apropos, the old French naturalist once cut 
the tapestried way of a group of processionaries 
who had gone out to take an airing by marching 
round the rim of a flower-pot near their nest. 
And, what do you think? Cut off from their 
way of retreat, the stupid things fell to circum¬ 
navigating the pot, going round and round on 
their silken trail; not one of them, though they 
must have been nearly famished, ever guessing 
that a trick had been played, and making almost 
no effort to strike out in a new path. Only nine 
inches from home and food, there they kept up 
their ceaseless, nosing march, till the afternoon of 
