Fig. 3 in On the affinities of Tetraceratops insignis, an Early Permian synapsid

Fig. 3. Reconstructions in palatal view of synapsid skulls. A. Dimetrodon limbatus Cope, 1877 (modified from Romer and Price 1940). B. Tetraceratops insignis Matthew, 1908 (modified from Laurin and Reisz 1996). C. Biarmosuchus tener Tchudinov, 1960 (modified from Ivakhnenko 1999). D. Gorgonops torvus Owen, 1876 (modified from Sigogneau 1970). The quadrate is colored in green, upper postcanines in orange, quadrate process of the pterygoid in yellow, and interpterygoid vacuity in brown (see arrow in D).