of the Skull in Peloneustes philarchus. 245 
about 1 centim. less, but behind this point there is a gradual 
increase in the width of the skull. 
1 \ 
i] \ 
occ. cond. 0 
Palatal aspect of a skull of Peloneustes, from a specimen (no, 4) in the 
Leeds Collection.—-7int.nar., internal nares; ma., maxilla; pm, 
premaxilla ; pal., palatine ; pt., pterygoid ; pas., parasphenoid ; p.for., 
posterior palatine vacuities; oc.cond., occipital condyle; 0, ridge on 
pterygoid; vo., vomer. 
The premaaille, which are separated from one another by a 
distinct suture, each bear six tooth-sockets, of which the first 
is the smallest and is directed forward and downward, the 
second is larger, the third and fourth the largest of the series, 
while the fifth and sixth decrease in size successively. None 
of the alveoli in any of the specimens retain the teeth, but at 
the hinder inner edges of several the tips of the young re- 
placing teeth are visible. The suture between the premaxilla 
and maxilla crosses the alveolar border immediately behind 
the sixth tooth and runs upwards and backwards on to the 
side of the rostrum in a curve, convex anteriorly. When it 
