Since beginning the study of the fossil crocodiles, about two years ago,2 one phase of that work in particular has challenged my attention, namely, that of the mechanical structure of the bones and its bearing on the life habits of these animals.
Some of the more striking characteristics of the vertebral column are here considered, and the advantages which may accrue to the crocodilian, as a result of them, are given first place in this discussion. These advantages may be a sufficient reason for the continued existence of the characters in question, but they do not, in themselves, explain the causes and origins; and, what is more, no attempt will be made to settle this question of derivation, which, I believe, no one fully understands. Most of the mechanical features which we have especially noted are such as to fit the crocodile to an aquatic existence and to the . . .