94 INSTINCT 
the occupant. In its nest Amphithe lies in wait for prey, 
ready to dart out upon any small creature which touches 
the ends of its long antenne. 
The activities of the adult Amphithce, with the exception of 
those concerned inreproduction, are almost exactly parallelled 
by those of its young. I have taken the eggs from the mater- 
nal brood pouch shortly before hatching and kept them 
isolated in individual dishes. For some time after emerging 
from the egg the young were weak and had imperfect control 
of their movements, which were jerky andirregular. Soon the 
minute creatures could crawl and swim much like the adults, 
and the next day they began constructing nests which were 
the same in shape as those formed by their parents. The 
attitudes in the nest, the waving of the antennz, the beating 
of the swimmerets, the restless movements of the legs and. 
mouth parts, springing after food, belligerency toward 
passers by, the little unobtrusive signs of timidity, the 
reversal of position in the nest on the approach of danger 
and the general behavior outside of the nest were, on the 
next day after hatching, almost exactly the same as in older 
individuals. The only differences in behavior were due to 
the feebleness of the young and their imperfect control of 
their movements. The young are hatched with all the 
instincts necessary fully to equip them for the business of 
life. No experience is necessary to teach them what is ad- 
vantageous for them to do. 
It is this skill and apparent foresight exhibited in instinc- 
tive behavior that gives rise to a popular notion that animals 
are somehow mysteriously endowed with a knowledge of 
those things which are necessary for their life. It is some- 
times asserted that young ducklings will make for the nearest 
water before they have gained any experience of the neighbor- 
hood and in the absence of any signs by which the presence 
