. Advances in herpetology and evolutionary biology : essays in honor of Ernest E. Williams. Williams, Ernest E. (Ernest Edward); Herpetology; Evolution. Proganochelys • Gaffney 193. Figure 2. Proganochelys quenstedti, SMNS 16980, ventral view of basicranium. at least part of the epipterygoid, but be- cause the suture is dubious, particularly in the ventral view, I am unable to de- scribe the portions formed by each bone. The recess has the form of a trough that is oriented anterodorsomedially and close- ly fits the opposing tubercle on the basi- sphenoid. The general form of the recess is simi
. Advances in herpetology and evolutionary biology : essays in honor of Ernest E. Williams. Williams, Ernest E. (Ernest Edward); Herpetology; Evolution. Proganochelys • Gaffney 193. Figure 2. Proganochelys quenstedti, SMNS 16980, ventral view of basicranium. at least part of the epipterygoid, but be- cause the suture is dubious, particularly in the ventral view, I am unable to de- scribe the portions formed by each bone. The recess has the form of a trough that is oriented anterodorsomedially and close- ly fits the opposing tubercle on the basi- sphenoid. The general form of the recess is similar to Captorhinus, but the recess faces more posteriorly in Proganochelys. The question of actual movement in the skull of Proganochelys must await the complete description of the specimens, but it is clear that some sort of movement was possible in the basicranial articula- tion. The akinesis of all turtles except Proganochelys results from a broad sutural fusion of the basisphenoid and pterygoid that I have interpreted (Gaff- ney, 1975) as a shared derived character testing the monophyly of the Casichely- dia. The recognition of the generalized amniote condition of the basicranial ar- ticulation in Proganochelys supports the argument that it (as the suborder Pro- ganochelydia) is the sister group of the Casichelydia. ACKNOWLEDGMENTS The opportunity to study the Triassic turtles in Stuttgart is due to the coopera- tion and support of Rupert Wild, Curator, and Bemhard Ziegler, Director, Staat- liches Museum fiir Naturkunde in Stutt- gart (SMNS). Wild spent many hours aiding me and my colleagues, and I am very grateful for his help and hospitality. I would also like to thank Karl-Heinz Fischer, Museum fiir Naturkunde, Ber- lin, for giving me access to the Jaekel Triassic material in East Berlin. Otto Simonis, Department of Vertebrate Paleontology, American Museum of Natural History (AMNH), performed the superb preparation necessary to expose the basicranial morphology of the
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Keywords: ., bookauthorharvarduniver, bookcentury1900, booksubjectherpetology
