It is indispensable, therefore, that the corporation of workers should not be dissolved while the stormy season continues and the insects are still in the caterpillar stage.

But, without special arrangements, each nocturnal expedition at grazing-time would be a cause of separation.

At that moment of appetite for food there is a return to individualism.
The caterpillars become more or less scattered, settling singly on the branches around; each browses his pine-needle separately.

How are they to find one another afterwards and become a community again?
The several threads left on the road make this easy.

With that guide, every caterpillar, however far he may be, comes back to his companions without ever missing the way.