external ear structure

[Darryl Jones <dinoguy@interlog.com>]

I am having some difficulty understanding how and where the tympanum
reaches the surface of the skin in dinosaurs.  I finally got Romer's
_Osteology of Reptiles_, which gives excellent descriptions of how the ear
works and what the inner structure looks like, but I am having trouble
figuring out how the tympanum connects to the surface.  Was it right on the
surface?  Was it in a notch?  Did it have a flap over it?

If I am understanding, the tympanum is connected to the quadrate.  part of
my confusion comes from the fact that in many theropods, the quadrate is
blocked almost completely by the quadratojugal laterally.  Is the external
ear (yes, I know that there was no real "external ear", but I am not sure
what else to call it) really that far back on the skull?  It looks like the
ear would have to be almost on the neck.  I have looked through all of the
papers I have to try to figure it out, but none of them show this.  I
gather it is something that everybody in the field just "knows", so they
don't bother putting it in papers.

If nobody feels like answering this question, could someone at least point
me in the direction of a paper I could get to figure it out myself.  Thanks
in advance.


Darryl Jones  <dinoguy@interlog.com>
                     <dinoguy@netscape.net>
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