Agassiz ultimately succeeded in classing the bones which had at first so puzzled him, into two divisions—interior and dermal; and the latter he divided yet further, though not without first lodging a precautionary protest, founded on the extreme obscurity of the subject, into cranial and opercular. Of the interior bones he specified two,—a super-scapular bone, (_supra-scapulaire_,)—that bone which in osseous fishes completes the scapular arch or belt, by uniting the scapula to the cranium; and a maxillary or upper jaw-bone. But his world-wide acquaintance with existing fishes could lend him no assistance in determining the places of the dermal bones: they formed the mere fragments of a broken puzzle, of which the key was lost. Even in their detached and irreducible state, however, he succeeded in basing upon them several shrewd deductions. He inferred, in the first place, that the _Asterolepis_ was not, as had been at first supposed, a cuirassed fish, which took its place among the Cephalaspians, but a strongly helmed fish of that Cœlacanth family to which the _Holoptychius_ and _Glyptolepis_ belong; in the second, that, like several of its bulkier cogeners, it was in all probability a broad, flat-headed animal; and, in the third, that as its remains are found associated in the Russian beds with numerous detached teeth of large size,—the boar tusks of Kutorga—which present internally that peculiar microscopic character on which Professor Owen has erected his Dendrodic or tree-toothed family of fishes,—it would in all likelihood be found that both bones and teeth belonged to the same group. “It appears more than probable,” he said, “that one day, by the discovery of a head or an entire jaw, it will be shown that the genera _Dendrodus_ and _Asterolepis_ form but one.” As we proceed, the reader will see how justly the ichthyologist assigned to the _Asterolepis_ its place among the Cœlacanths, and how entirely his two other conjectures regarding it have been confirmed. “I have had in general,” he concluded, “but small and mutilated fragments of the creature’s bones submitted to me, and of these, even the surface ornaments not well preserved; but I hope the immense materials with which the Old Red Sandstone of Russia has furnished the savans of that country will not be lost to science; and that my labors on this interesting genus, incomplete as they are, will excite more and more the attention of geologists, by showing them how ignorant we are of all the essential facts concerning the history of the first inhabitants of our globe.”