172 
NATURE STUDY. 
Woodpecker Architecture. II. 
BY EDWARD J. BURNHAM. t 
If the sluggard may learn a lesson in industry from the 
ant, the student of nature who rejoices in well-directed ex¬ 
penditure of energy will find great pleasure in the contem¬ 
plation of a woodpecker’s nest. As suggested in a previ¬ 
ous paper, the amount of labor involved is prodigious. 
The nest of the Hairy woodpecker is at the bottom of a 
vertical tunnel, nearly regular throughout its length, four 
inches in diameter, and varying from six to eight inches 
in depth. The cut (Fig. 1) gives an impression of irregu¬ 
larity, from the fact that the section of the 
tree was not divided equally, and our ar¬ 
tist sketched the museum specimen as it 
appeared. The nest of the Downy wood¬ 
pecker is somewhat smaller and less regu¬ 
lar, but the bird is smaller, and is, perhaps, 
not quite so skilled a workman. 
These nests are excavated in trees which 
are dead, or nearly so, but whose wood has 
not yet been much softened by decay. Just 
how the woodpecker manages to make the 
tunnel is a matter of conjecture. There are obvious diffi¬ 
culties in the way of satisfactory observation of a bird con¬ 
cealed in a limbless trunk at an elevation of twenty or 
thirty feet from the ground. It appears probable, how¬ 
ever, that he clings to the side of the shaft, with his head 
downward, moving round as he pecks away—a conjecture 
that seems to be strengthened by the shape of the tunnel 
at its lower end, which is hollowed in the center, like the 
bottom of a cup. It is possible, of course, that this hol¬ 
lowing may be due to instinct, rather than to the method 
of excavation, since it is plainly an advantage that the eggs 
Fig.i. 
