WOODPECKER ARCHITECTURE. 
73 
should tend to roll together, and that the featherless young 
should be huddled in a bunch ; and this cup-like form is 
common to the nests of most birds. The objection may be 
made, also, that woodpeckers do not usually run about upon 
trees head downward, as do the creepers; an objection 
which may perhaps b.e met by reference to the roughened 
or furrowed condition of the sides of the tunnel, possibly 
enabling the little workman to cling in an otherwise im¬ 
practicable position. Unquestionably the safest course is 
to admit that we do not know where the woodpecker stands 
while excavating the vertical shaft, after he has progressed 
several inches below the entrance. So far as we have been 
able to ascertain, a thorough comparative study of a wood¬ 
pecker’s foot with reference to his capacity for vertical tun¬ 
neling still remains to be made. 
But while we do not know how the plan of the architect 
is brought to completion, we may easily become familiar 
with the finished work, for abandoned nests are to be found 
in any forest or patch of woodland that, contains trees suit¬ 
ed to the woodpecker’s taste or capacity for drilling. The 
‘ ‘hairy’ ’ is perhaps the most thorough work¬ 
man of all the woodpecker tribe. His home 
is spacious and substantial, suggesting the 
idea that in its construction economy of 
labor was a secondary consideration. The 
entrance is circular, about two inches in 
diameter—more rather than less—and the 
tunnel goes straight down for six, seven, or 7 
even eight inches. The roof presents the 
appearance of a Roman arch, the wood hav¬ 
ing been cut away evenly from the'entrance 
to the extreme opposite side. The ‘ ‘downy’ ’ 
Fig. 
2. 
is not quite so careful with the sides of his tunnel, which 
are somewhat irregular (Fig. 2), and in the shape of his 
roof he affects the Gothic style. He may pretend to his 
