The longest feathers or primaries (PR) are borne by the two fingers (2 and 3), and their palm-bones (CMC); the second longest or secondaries are borne by the ulna bone (U) of the fore-arm; there is a separate tuft (AS) on the thumb (TH).
- Author
- The Project Gutenberg EBook of The Outline of Science, Vol. 1 (of 4), by J. Arthur Thomson
Published in 1922
Available from gutenberg.org - Posted on
- Thursday 16 July 2020
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