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ERIK A : SON STENSIO 
P. 176 — P. 186, P. 697, P. 881), of which some are even so well preserved that they 
afford us a fairly good idea of the appearance and general proportions of the animal, 
which, as we have already partly seen, is not often the case with the fishes from the 
Triassic of Spitzbergen. 
The largest specimens known attained a length of 25— 3 o cm, the smallest about 
7 cm. Compared with the length the height is rather considerable; in specimens P. 189 
(PI. 33 ) and P. 176 (PI. 35, fig. x) it is, however, larger than it was in reality, because 
of the state of preservation. The greatest height is situated considerably in front of 
the dorsal fin about half-way between this and the head and is apparently from about 
a third to a quarter of the total length. Posteriorly towards the tail the height decreases 
rather rapidly both dorsally and ventrally, and both the dorsal and the ventral outlines 
seem therefore fairly strongly convex, the former, however, more than the latter. The 
length of the head seems to be from a quarter to a fifth that of the whole fish. 
The membrane bones of the neurocranium. 
There where undoubtedly ossifications in the primordial neurocranium, but no 
details are known as to these. The membrane bones, on the other hand, are partly well 
preserved. 
The parietals (Pa, text figs. 80, 81; PI. 34, figs. 1, 2) are, as Woodward has already 
mentioned, developed symmetrically and have an almost square shape. They seem to’ 
have met in a fairly straight median suture. The frontals (Fr, text figs. 80, 81; PI. 33 ; 
PI. 34, figs. 1, 2) also seem to have been fairly symmetrical. Their width is rather great 
and, at its greatest point, is about half the length. The medial margin is rather straight. 
The lateral one, on the other hand, has a projecting corner, by which it is divided into 
an anterior and a posterior part, both of which are concave. Against the posterior part, 
which is the shortest, is situated the anterior part of the supratemporo-intertemporal 
(Stemp.it., text figs. 80, 81; PI. 34, figs. 1, 2), which is long and narrow. (For its homologues 
see pp. 1 38 , 242 above). The extrascapulars are represented only by a single rather large 
plate (Ext, text figs. 80, 81; PI. 34, figs. 1, 2) on either side of the median line. In front 
of the supratemporo-intertemporal, along the anterior part of the lateral margin of 
the frontal, there are some supraorbitals (So, text figs. 80, 81; PI. 33 ), which are, 
however, crushed and poorly preserved, so that their number cannot be established with 
certainty. The most posterior of them seems, as we shall see from the course of the 
infraorbital canal, to correspond most closely to the dermosphenotic. 
The ethmoidal region is preserved only in two specimens (P. 166 and P. 477), but 
is partly crushed in both. Its anterior end has been blunt with an indication of a 
rostrum as in the Palaeoniscids, but it is impossible to decide whether the profile was 
exactly as I have shown it in my reconstruction in text fig. 81 or still more blunt. 
In the roof of the ethmoidal region anterior to the frontals there is a rather long 
and relatively narrow unpaired bone-plate (Na. ptr, text fig. 80, 81; PI. 34, figs. 1, 2), • 
which is bent in a characteristic way, indicating that it not only covered a part of the 
dorsal surface of the region but also a considerable part of the anterior one below the 
anterior extremity of the rostrum in the way shown in text fig. 81. The anterior part 
of this bone-plate is pierced by the ethmoidal commissure of the infraorbital canals and 
