Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/124

38 pula and the coracoid, and the crested and broad sternum, of the Pterosauria are marks of affinity with birds, as strong as those which the hind limb and pelvis present in the Ornithoscelida. But I think this argumentation is invalid; for the shoulder-girdle of an ostrich or of an apteryx is more similar to that of an Ornithoscelidan than it is to that of a Pterodactyle, these special peculiarities of the shoulder-girdle, like the crest of the sternum, having relation to physiological action, and not to affinity. If the strongly crested sternum and the acute angulation of the union of the scapula and coracoid were marks of ornithic affinity, they would be found in all birds. The contrary is true: they are found only in those birds which fly; and the crest exists in bats, which cannot be said to have any affinity with birds.

On the other hand, the peculiarities of the hind limb and pelvis which the Ornithoscelida share with birds are found in all birds. It may be said that all birds stand upon their hinder feet, and that, as the Ornithoscelida did the same, the resemblance of structure arises from a resemblance of function. But I doubt if the majority of the Dinosauria stood more habitually upon their hind limbs than Kangaroos or Jerboas do; and unless there was some genetic connexion between the two, I see no reason why the hind limbs of Ornithoscelida should resemble those of birds more than they resemble those of kangaroos.

Finally, with regard to the sternum, although there is no likelihood that the Ornithoscelida possessed a crested sternum, yet there is some evidence that they were provided with a very broad and expanded breast-bone, more like that of a bird than it is like that of any reptile. I shall discuss this evidence below, in speaking of the Dinosaurian remains discovered by Plieninger in the Trias near Stuttgart.

The first recognition of the occurrence in the Trias of Dinosaurian remains as such, with which I am acquainted, is contained in the following extract from a letter, addressed by H. von Meyer to Bronn, and published in the ' Jahrbuch' for 1857.

"Dr. Engelhardt, of Nuremberg, brought to the meeting of Naturalists in Stuttgart some bones of a gigantic animal from a brecciated sandstone of the Upper Keuper of his neighbourhood. He had the kindness to submit to me all the bones which had been obtained. I have already examined them, and have drawn the best, which consisted of almost entire limb-bones and of vertebræ.

"The discovery is extremely interesting. The bones belong to a