Note 159 — Chapter XXXIII · ARTHRODIRES
Reading edition
It will be recalled that there is no ground for concluding that the "mandibular rami" possessed an endoskeletal core, and were comparable, therefore, to the somewhat mobile jaws of Elasmobranchs. On the other hand, there is the strongest evidence that they are entirely comparable to adjacent dermal plates. Histologically they are identical, and in certain cases their exposed surfaces bear the same tuberculation.