choristoderes non-Saurian?

["Ken Kinman" <kinman@hotmail.com>]

    I just started reading David Dilkes 1998 analysis of basal 
archosauromorphs (in his _Mesosuchus browni_ paper).
    He does not even put choristoderes in Sauria (much less 
Archosauromorpha).  Two characters which he uses to exclude choristoderes 
from Sauria are (1) the primitive lack of crista prootica, and (2) the 
"shape of the ectopterygoid along suture with pterygoid" being tranversely 
broad (also a primitive state).
 Questions:
      (1) Are either of these characters strong enough to exclude 
choristoderes from the Sauria?  Are crista prootica ever lost secondarily 
among Saurians?
      (2) Can anyone tell me if these character states are primitive 
(non-Saurian) in turtles?

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