PANTYLUS CORDATUS COPE 22 
midway. ‘Thisis essentially as Case has figuredit.t The lachrymal 
extends back from the nares in a broad triangle and forms the 
entire anterior border of the orbit. It forms the floor of the front 
half of the eye cavity and extends inward nearly to the nares. 
The arrangement of the palate bones, so far as one can make it 
out, is much the same as that in Captorhinus. The premaxillary 
is probably short and does not enter very largely into the internal 
nares. The prevomers are rather broad and well developed. They 
lie along the inner side of, and extend nearly to the posterior border 
of, the nares. The pterygoids, of which the posterior end is missing 
on both sides, send forward rather broad processes that converge 
in a gentle curve and meet at a point a little back of the posterior 
border of the orbits. From this point they extend forward, gradu- 
ally narrowing and separating the prevomers fully half their 
length. In cross-section the pterygoids are angular, one side lying 
in the plane of the palate, the other extending vertically nearly to 
the cranial roof. Back of the nares and forming their posterior 
border lie the broad, platelike palatines. They extend inward 
toward the median line, underlying the pterygoids and extending 
upward along the inner angle of these bones. The transverse bones, 
if present, are indistinguishable. 
Dentition.—While the upper dentition is probably not complete 
in this specimen, the essential features are readily made out. The 
premaxillary bears two teeth, the first of which is the larger, 4 mm. 
or more in diameter. The maxillary bears eight teeth and probably 
about four more of the posterior ones are broken away. ‘The first 
two of these exceed those following in diameter and height, the sec- 
ond being the larger of the two and measuring but little less than 
the first premaxillary tooth. The remaining maxillary teeth are 
slightly oval in cross-section rather than circular and are sub-equal 
in diameter and height, these measurements being about 2 mm. and 
2.5mm. respectively. The prevomer region of the palate was 
exposed from above as the matrix below was very hard and was 
protected by the anterior part of the mandible. Hence it cannot 
be said with certainty whether the prevomers bear teeth or not, 
but in all probability they do. On each palatine there is a large, 
t Publication No. 145, Carnegie Institution of Washington, p. 114, Fig. 52c. 
