TRIASSIC FISHES FROM SPITSBERGEN 
99 
plates consists of longitudinally placed striae, which in size and length correspond most 
closely to those of the scales. 
The visceral skeleton. 
The autopalatine is incompletely preserved and it is not impossible that this is due 
to a slight development of the bone itself, but one cannot form a definite conclusion 
from the material at hand. 
The quadrate ( Qu, text fig. 45 A, B; PI. u; PL 15, figs, x, 2) covers, as usual, the 
ventrocaudal corner of the pterygoid on the lateral side. It has a very thick posterior 
part that can conveniently be called the corpus and a lamella that issues from the 
anterior border of the corpus. The centre of ossification lies in the ventral part of the corpus. 
The corpus (PI. 15, fig. 2) is rather high, but its longest axis does not stand vertically 
but slopes a little backwards. Its greatest breadth, which is about the same as half its 
Mptg, metapterygoid; Pt, pterygoid; Qu, quadrate. 
15 ) The bones of the palatoquadrate with the cartilage connecting the metapterygoid and the quadrate restored. Lettering as in fig. A. 
height, is at its upper end. From here it gradually grows narrower in the ventral direction, 
while at the same time it decreases a little in thickness up to the vicinity of the ventral 
end, where it swells out to a condyle for the articulation with the mandibula. This end 
is somewhat rounded, but otherwise it is too imperfectly preserved to make a closer study 
of the shape of the articulating surface possible. The dorsal end is, on the contrary, abruptly 
truncated, and extends posteriorly a little beyond the caudal margin of the pterygoid as 
in W. sinuosa and the majority of the Coelacanthids. While the part of the corpus lying 
on the ventral side of the centre of ossification, i. e. the condyle, is formed of compact 
bone, the remaining part dorsally of the centre of ossification has, on the contrary, been 
partly cartilaginous in its interior and united dorsally to cartilage. The anterior lamella, 
the shape and position of which are quite clear from text fig. 45, is united to the corpus 
for pretty nearly the whole of its height. 
The metapterygoid {Mptg, text figs. 45, A, B; Pis. 11, 12; PI. 15, figs. 1, 2) is a 
rather large and thick bone, which, as in the case of W. sinuosa and S. tuberculata, covers 
