162 UPPER CRETACEOUS TELEOSTS 
extends back beneath the anterior parasphenoid region. Whether the vomer is 
toothed could not be seen. 
Within the postero-ventral region of the orbit there is a long basisphenoid pedicel, 
but no evidence of an orbitosphenoid could be seen. At the anterior end of the 
snout a small nasal bone lies lateral to the anterior region of the frontal and extends 
on to the dorsal surface of the mesethmoid. 
Infraorbital bones. A circumorbital ring of bones is present although they are 
poorly preserved and fragmentary. There are five or six bones in the series, 
including the lachrymal. The bones are narrow and roughly equal in size except 
for the lachrymal which is larger. The bones are grooved laterally for the infra- 
orbital sensory canal. The last infraorbital articulates with the sphenotic. Dorsal 
to the lachrymal is a further bone which probably represents an antorbital. The 
lachrymal and the first infraorbital show signs of having possessed a slight subocular 
shelf. 
Hyopalatine bones. The hyomandibular is slender and vertical with a single 
articulatory head. The opercular process is small, in the upper third of the bone, 
and covered laterally by the preoperculum. Anteriorly the hyomandibular is thin 
but its posterior edge is considerably thickened. Just within the upper half of the 
posterior edge is a short process projecting postero-laterally from the crest which 
runs along the posterior edge of the bone. The hyomandibular tapers ventrally and 
a stout symplectic bone connected it with the quadrate. The symplectic is attached 
Fic. 74. Pattersonichthys delicatus gen. et sp.nov. Restoration of the skull in lateral view. 
From B.M.N.H. number P.9977a. 
