. Carnegie Institution of Washington publication. MORPHOLOGICAL REVISION OF THE SUBORDER. 153 posterior than the inner. The long axis of the condyles is inclined somewhat inward. The outer condyle is extended backward, as in Dimetrodon^ forming a sort of shelf on which rests the lower end of the quadrato-jngal. The qiiadrato-jitgal and prosqitamosal occupy the same relative positions as in Dimetrodon. The first rests against the posterior edge of the quadrate and overlies the posterior edge of the prosquamosal. There are indications that a quadrate foramen was present, but it is closed in the
. Carnegie Institution of Washington publication. MORPHOLOGICAL REVISION OF THE SUBORDER. 153 posterior than the inner. The long axis of the condyles is inclined somewhat inward. The outer condyle is extended backward, as in Dimetrodon^ forming a sort of shelf on which rests the lower end of the quadrato-jngal. The qiiadrato-jitgal and prosqitamosal occupy the same relative positions as in Dimetrodon. The first rests against the posterior edge of the quadrate and overlies the posterior edge of the prosquamosal. There are indications that a quadrate foramen was present, but it is closed in the specimen, perhaps by pressure. Superiorly, the quadrato-jugal passes below the lower ends of the squamosal and a second bone, the epiotic (?). The anterior end of the prosquamosal is broken away, but it reaches up as far as the upper edge of the quadrate, touching the lower end of the squamosal. The squamosal is a thin and slender element convex in curvature, which joins the parietal above and the quadrato-jugal and the prosquamosal below. At its lower end a wide process started forward toward the postorbital, but this is broken so that its anterior connections can not be made out. The j^rocess evidently is a portion of a bridge across the temporal vacuity; Cope considered that there was but one such bridge and that the animal had a single temporal arch, but the condition of the speci- men makes probable the possibility of the presence of a second arch Fig. 68.—Diagram of the lateral surface of the skull of Edaphosaurus pogonias. Fig. 69.—Diagram of the posterior surface of the same. Lettering as in figs. 66 and 67. Epiotic if): Below the parietal and interparietal and above the posterior wall of the cranial cavity is a pair of slender bones that curve outward and downward; lying next to the lower edge of the squamosal they extend outward and downward until they touch the upper ends of the quadrato-jugal. These bones are in the exact posi- tion of the epiotics, and
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