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PROCEEDINGS OF THE NATIONAL MUSEUM 



dentary were drawn from the elements of the left side. The form and 

 size of the orbit are clearly outlined in the matrix, although all the 

 surface bone of the jugal, lachrymal, and prefrontal is missing. The 

 diminutive size of Paraglyphanodon gazini is well illustrated by 

 the skull, which has an estimated length over all of 26 mm. 



Viewed from above, the parietal minus the posterior processes, the 

 right frontal, small portion of the left, and part of the right post- 

 frontal are present in their natural relationships. The coalescence of 

 all sutures except those joining the nasal bones renders it impossible 

 clearly to delimit these separate elements. The premaxillary region 

 is missing. 



The parietal has the usual quadrangular outline, with an undulating 

 superior surface that appears to be perforated by a pineal foramen 

 near its junction with the frontals. Whether this foramen lies wholly 

 within the parietal or whether it is bisected by the frontoparietal suture 



Figure 7. — Skull and lower jaw of Paraglyphanodon gazini viewed from the right side: 

 ar, Articular; co, coronoid; d, dentary; /, frontal; ju, jugal; mx, maxillary; p, parietal; 

 pmx, premaxillary; pof, postfrontal; qu, quadrate; sur, surangular. X3. U.S.N.M. No. 

 16580 (type). 



cannot be determined from available materials. On the posterior bor- 

 der of the parietal the upper surface is excavated, thus forming a nar- 

 row transverse shelf that is divided into two halves by a raised longi- 

 tudinal ridge at the center. Between the supratemporal fossae the 

 parietal has a least transverse diameter of 7.5 mm. 



The frontals are paired. On the superior outer edge of each frontal 

 a low, raised, longitudinal ridge extends the greater length of the 

 bone. 



A portion of the right postfrontal is preserved in the type, but the 

 coalescence of the sutures makes it impossible to determine its manner 

 of junction with the parietal and frontal. 



The right quadrate is preserved in articulation with the ramus as 

 shown in figure 7, but its poor preservation renders all structural details 

 obscure. 



