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postorbitals take part in the formation of the orbits behind. They 
are united with the postfrontals and parietals above, behind by a 
process with the prosquamosal and below with the jugal. The jugal 
is a large bone which borders the orbit below. In front it is joined 
to the lacrymal and the posterior process of the maxillary, above to 
the postorbital and behind to the quadratojugal. A strong ridge on 
the lower side bears a face for the ectopterygoid. The quadrato- 
jugal is placed between the jugal and prosquamosal and covers the 
quadrate externally. Between the quadrate and quadratojugal, in 
front, a deep pit is present, which represents the foramen between the 
quadrate and quadratojugal in Sphaenodon. The prosquamosal 
overlaps the quadrate behind, nearly reaching the articular face. It 
is separated from the distal end of the quadrate by a posterior pro- 
cess of the quadratojugal, which extends as a wedge between them. 
It shows on its upper posterior surface a strong ridge. It is united 
above with the postorbital and on its internal lateral face with the 
squamosal by a straight suture. The squamosal covers the re- 
maining portion of the quadrate behind and wraps around its inner 
edge, to appear on its anterior face. 
The quadrate is a most peculiar bone. It is entirely covered 
on the superior and lateral surfaces by the quadratojugal, prosqua- 
mosal and squamosal. A small part of the anterior portion, the re- 
gion of the pit, is seen between the squamosal and quadratojugal- 
The articular face for the lower jaw is divided, by a longitudinal ridge, 
into two long, parallel, deep grooves. . These grooves are directed in- 
wards at an angle of about 45° to the main axis of the skull. 
The cranium is formed by the union of the basioccipital, ex- 
occipitals, supraoccipital, the very large paroccipitals, and the petrosals'). 
The basisphenoid is completely free from the basioccipital; the 
connection was, without any doubt, by cartilage. It shows a well 
developed, vertically expanded presphenoid portion. The basipterygoid- 
processes are very short, close together and show distinct articular 
faces, which were covered with cartilage, for the pterygoids. The basi- 
sphenoid is excavated below and behind by a very large fossa. 
The following elements of the palatal region are preserved: both 
the pterygoids (the left nearly complete); the palatine of the left side, 
lacking the posterior portion and parts of the right one. No traces 
of the vomers have been found. 
1) The „stapes“ described and figured by Corz, in Clepsydrops 
leptocephalus, is a rib. 
