Note 5 — X. WHERE BIRDS ROOST.

The reader will see, from the facts given in the remainder of the chapter, that I reckoned without my host in supposing that woodpeckers usually sleep in cavities of trees. That they sometimes select such places for roosts cannot be doubted; but that such is always or even generally their habit the experiments described farther on conclusively disprove. It is only fair to say that the rest of the chapter was added long after the foregoing had been written, and proves how unsafe it is for the naturalist to make generalizations.