TRIASSIC FISHES FROM SPITZBERGEN 
63 
or, according to Huxley’s view (1866, p. 34) as the squamosal + the post-temporal. 
I myself must, on grounds which I shall give later on, propose new terms for the two 
bones under consideration. The longer anterior one I shall call in the continuation the 
parieto-intertemporal, the posterior one the supratemporo-extrascapular. 
In W. sinuosa the parieto-intertemporal bones are only imperfectly preserved, as 
their median and posterior parts are totally missing. Under such conditions one cannot 
define their precise extension backwards but an eventual deviation in this respect from 
my restoration in text fig. 21 may not be very important. The parieto-intertemporais 
ought to have been of a rectangular shape, and in breadth were probably rather more 
than half the length. At the postero-lateral corner each of them has a large sinus into 
which the supratemporo-extrascapular (Stemp. ext) fits. The centre of ossification of 
each parieto-intertemporal bone lies near the antero-lateral corner. 
A perpendicular longitudinal lamella, which covers a stretch of the upper cartila¬ 
ginous part of the labyrinth region on the lateral surface, issues on the ventral side 
a little medially of the lateral margin of the anterior part pf the parieto-intertemporal 
(text fig'. 19). With its ventral border this lamella anteriorly comes very near to, or 
even in touch with the process f, on the prootico-opisthotic and the dorsal parts of the 
basisphenoid. The horizontal part of the bone, which lies laterally of the line along which 
the perpendicular longitudinal lamella issues, is always in the Coelacanthids pierced 
by a sensory canal, but this canal has not been preserved in the species here under 
consideration. 
On each postero-lateral corner of the dermal cranial roof the supratemporo-extra¬ 
scapular bone forms a powerfully projecting process [Stemp. ext, text figs. 19, 20, 21, 25; 
PI. 4, fig. 1; PI. 5, fig. 1; PI. 6, fig. 4; PI. 8, fig. 1). Seen from the lateral side the 
supratemporo-extrascapular (text fig. 19) is shaped like a triangle with the apex pointing 
backwards and the base partly in connection with the parieto-intertemporal bone. The 
antero-ventral corner is extended to a long antero-ventrally and at the same time some¬ 
what medially pointing process (h), which covers the postero-dorsal corner of the antero¬ 
lateral side surface of the prootico-opisthotic. In dorsal aspect the supratemporo-extra¬ 
scapular bone appears to have a somewhat more complicated form (text fig. 21 A). One 
can observe, as before, its lateral surface, but it is now. clearly understood that the 
direction of this surface is not purely lateral, but is also somewhat dorsal and even 
partially rostral; the process h can also be observed from the dorsal side, and the 
relation it bears to the prootico-opisthotic. Furthermore one finds a dorso-medial surface, 
which is only developed in the posterior part of the bone and of course is a good 
deal smaller than the lateral or, as it ought perhaps to be called, the dorso-lateral one. 
While the anterior part of the bone laterally occupies such a position that it 
forms nearly a direct posterior continuation of the perpendicular longitudinal 
lamella of the parieto-intertemporal bone and also, like that lamella, covers a dorsal 
and anterior part of the cartilaginous side wall of the labyrinth region, on its lateral 
surface this relation is changed posteriorly in such a way that the posterior half of 
the bone rests instead totally upon the dorsal surface of the same region. A transverse 
section of this posterior part, which shows plainly the relation between the dorso-medial 
and the dorso-lateral surface and at the same time makes it evident that the thickness 
