Some of the quills measure fully 5 in.
This, the stretcher of the cubital quills, is a very interesting muscle.
the short tail, tipped with numerous slender-stalked open quills, which make a loud rattling noise whenever the animal moves.
The young (which on leaving the nest have not the tips of the bill crossed) are of a dull olive colour with indistinct dark stripes on the lower parts, and the quills of the wings and tail dusky.
The last dozen vertebrae each carry a pair of well-developed typical quills.