QUOTE (Ernest Friedman-Hill @ Jan 2 2010, 03:34 AM)

This image is really too small for meaningful critique....
It would have made an
excellent postage stamp

Seriously, though, Ernest has given very good advice here. If I can add in one suggestion in support of his comments:
QUOTE
the outline seems somewhat simplified -- corners rounded over, angles softened
I think these's a lot to be said in favour of plotting out proportions and placements, and getting down the basic shapes first in
straight lines, rather than in curves. This forces one to try to see the shapes as runs of straight lines which bend at particular inflection points, rather than as soft "mushy" curves. (Obviously, one then softens things to curves where needed).
This approach can help get the shapes accurate, rather than just getting generic curves. Think about the underlying anatomy, and how in some places bones come close to the surface, while in other places the tissues are soft, and are either slung between bony points (think of it as like drapery, or like a suspension bridge), or stretched under tension.
I'd add that the drawing is pretty good, but could be so much more dynamic and powerful with some relatively minor alterations in approach.
Dave