QAO PROCEEDINGS OF THE NATIONAL MUSEUM VOL, 92 
They are bounded outwardly by the maxillary and ectopterygoid, in- 
wardly by the pterygoid and palatine, in front by the palatine, and 
behind by the pterygoid and ectopterygoid. 
The palatonares, also paired vacuities, are long and narrow, bounded 
externally by the maxillary, internally by the vomer and palatine, 
posteriorly by the palatine. 
In addition to these usual openings, the vomer is perforated near 
its anterior end by a small foramen, and there appears to be an aperture 
through the palatine near its posterior end. 
The palate of Polyglyphanodon in its general design resembles that 
of the Jguana, especially in the robustness of the downwardly project- 
ing pterygoid process, and the stout ectopterygoid and the manner of 
its attachment to the posterior end of the maxillary. It differs in the 
much reduced size of the pterygomaxillary vacuities, and the more 
posterior position of the palatine processes that unite with the 
maxillary. 
Measurements——Comparative skull measurements (in millimeters) 
are as follows: 
Type Paratype 
Greatest length over" alls sec ee oe a Se 81.5 80.0 
Greatest width across tops: of quadrates___---~-- =. 5 == 45. 0° 52.0 
Greatest width aeross! jugals 2.22222 Soe) oe ee ee eo See 58. 5 
Greatest width across: center of mares. eee ee ee 14.0 14. 0 
Least width of parictal-at, centeris=—2-) _ 2222 o 22 ee See 9.5 8.5 
Least width of frontal at center] 22 = ae ee ee 11.0 12.0 
Greatest height of skull with lower jawSs ses. -—--- === 60.8 ere! 
Diameter of orbit anteroposteriorly_2 2-2 {ee ee ee PAE 
Vertical diameter Of Orbit 22 a2 Ses ee ee ee eet nes ae 210 
Greatest leneth; of quadrate 2s = ee ee eee bl i Sey 
Greatest lengthvof squamosal == 22a Se ee ee ee ee 16. 0 
Greatest wiength sob frontal==- 22 Se ee ee ee 352 32.2 
Greatest length of parietal 22 2. 2 ee eee ees 19.0 
Greatest width, of occipital condyle_-= == sae ee 9 bi Li 
e=estimated 
LOWER JAW 
The rami of the type specimen are in excellent preservation and in 
articulated position with the skull, but many of the sutures are in- 
distinct. In all there were seven other rami in the collection, and from 
a study of all it has been possible to delimit most of the individual 
elements of the mandible and to determine it as consisting of six 
distinct bones: dentary, angular, surangular, articular, coronoid, and 
splenial. It is assumed that the prearticular is present but fused with 
the articular, as it is in most adult lizards. 
The ramus asa whole is strong and massive, deepest at the center and 
narrowing toward the ends. 
