RE: anatomical questions (mandibule of a basal synapsid)

[Michael Mortimer <mickey_mortimer111@msn.com>]

Jeff Leach wrote-

> 1) is the retroarticular process the ventral process of the articular (as 
> labeled in the figure)? The shape and position differs from therapsids so I 
> am somewhat unsure.

No, the retroarticular process is the part posterior to the mandibular 
articulation (X and Y).

> 2) is the 'cotylus for the quadrate' the posterodorsal corner of the 
> articular (about where 'art' points to in the medial view of the 
> mandibule?)

No, the cotylus for the quadrate is X and Y.  A cotylus is just an 
articulating concavity, and as you deduced in question 3, those cotyla are 
where the quadrate articulates with the mandible.

> 3) The two fossa labeled X and Y, anyone know if they have names? They look 
> like the articulating surfaces for the quadrate.

See above.

> 4) the article refers to the 'external mandibular foramen', 
> 'inframandibular foramen' and 'meckelian fenestra'. The last two terms are 
> equivalent, at least I think so. Have I labeled the mandibular foramen and 
> inframandibular foramen correctly.

The external mandibular foramen (or fenestra) is the dark gray and white 
hole in lateral view.  I would agree the other two terms are probably 
equivalent, and are the dark gray hole in medial view.

> 5) Is the 'coronoid eminence', the portion of the posterior coronoid 
> visible in lateral view or does it continue posteriorly along the 
> surangular?

I'd say the second possibility.  Oviraptorids have a coronoid eminence on 
their surangular that their coronoid (which is barely present) doesn't even 
participate in.

Mickey Mortimer