46 THE ARCHITECTURE OF BIRDS. 
Among these carpenteros they rank the toucans 
(Ramphastide), but whether they are correct in this 
it is difficult to decide, in the absence of any very 
accurate evidence. The bill of the toucan, indeed, 
seems, upon a. slight inspection, to be sufficiently 
powerful for the task assigned it; but it is found on 
examination to be much inferior in strength to that 
appearance of it which is indicated by its size. If it 
were not, indeed, of light materials, it would be im- 
possible for the bird to carry its head. It is not 
solid, but full of reticular cells,as thin as paper, 
over which Dr. Traill, of Liverpool, has shown that 
the nasal nerves are expanded. Yet the universal 
opinion of the people where these birds are indige- 
nous is, that it‘employs its large bill in the forma- 
tion of a nest in the trunk of a decayed tree. Wil- 
lughby, speaking of its resemblance to the wood- 
peckers, says, “‘it not only hath a like situation of 
toes, but also in like manner hews holes in trees to 
build its nest in.” ‘‘ Faber,” he adds, “doth nat 

Head and Bill of a Touean (Ramphastos Toco). 
