Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/863

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body; and the jaws do not appear to have borne teeth. The backbone has a few more than thirty -joints, of which about seventeen belonged to the ventral vertebras ; but the number of the vertebrae cannot be distinctly reckoned.

" Satisfactory information cannot be given respecting the pectoral fins. Behind the gill-covers a somewhat waved ribbon-shaped organ runs in a sloping direction backwards to the ventral margin, which perhaps might be the humerus ; and at its root one sees some bones which one is inclined to take for the roots of the pectoral rays. But this ribbon-shaped organ is provided with distinct parallel longitudinal striae, and itself resembles a pectoral fin ; and those bones we took for roots of the pectoral rays might be apophyses of the vertebral column displaced by pressure.

" The little elliptical ventral fins are nearly behind the middle of the belly, and not in immediate connexion with other bones, and may perhaps, through pressure or dislocation, have been pushed backwards ; but at any rate they are placed behind the pectorals. The anal fin itself is not to be seen ; but the root-bones (fin-supports), which are present, show that it commenced close to or not far from the ventrals, and extended for a considerable distance towards the tail.

"The dorsal commences a little before the middle of the back, quickly gets narrower towards the apex, and continues in a vertical direction, with pretty equal breadth, to the tip. It has in this example, on the hinder side at the base, a bow-shaped emargination, which, however, may not have been caused by tearing or injury, because the rays do not break off, but run in parallel curves to the root. The support-bones also show that the dorsal did not extend more behind than before, and that we have the dorsal fin perfect and complete before us. The existence of a second dorsal cannot be directly denied, because in the place where it should appear the fish becomes obscured by the stone, and there are no sharp lines ; but occasionally one can see the outline of the back so clearly that one would certainly see bones if there had been a second dorsal ; and we may therefore conclude that, in all probability, it was absent. "The caudal is forked; both lobes are equal, and are separated by the backbone.

"It is all the more difficult to determine the family to which this fish belongs, as neither scales nor teeth are to be seen. The rhombical markings which the figure shows near the tail, and which one might take for scales, have no glistening surface, and appear more as fragments of ribs and spinous processes crossing each other. If they were really scales, the genus Dorypterus would then belong to the Ganoids, and stand near Dapedius. But the form, the situation of the fins, and the whole skeleton remind one very much of the recent genus Vomer."

Although Prof. Germar's specimen was not perfect enough to enable him to describe it fully, yet in the foregoing description we find a sufficient number of characters to justify us in referring our specimens to this peculiar fish. Among these the position of the