2nd. That the foot-prints of Chirotherium are at least as much like those of certain Toads as those of any other animals.
3rd. That the size of the known species of Labyrinthodon corre sponds with the size of the foot-prints of the different species of Chirotkerium ; e.g. Labyrinthodon Jageri, with the foot-print of Chirotherium lIercules (Egerton); 'Labyrinthodon paehygnathus, with the foot-marks of the common Ckirotherium ; aud Labyrinthodon leptognatkus with the impressions of the smaller Batrachian figured in the memoir by Sir Roderick Murchison and Mr. Strickland.
4th. Labyrintkodon occurs in the Now Red-Sandstone strata to which Chirotherian impressions are peculiar. And Lastly, no remains of animals that could have left such impressions as those of the Chirotherium have been found in these strata, except the remains of the Labyrinthodon.
It is true that the structure of the foot is still wanting, a mole connected and complete skeleton is required for demonstration.; but the circumstantial evidence above stated is strong enough to produce the conviction that Chirotherian and Labyrinthodontic foot impressions are identical; and that Maatodonsaurus, Salamandroidea, Phztagaurua, Chirotherium, and Labyrinthodon are one and the same genus, which ought for the future to be designated by the last mentioned name. We owe this evidence principally to the use of the
microscope in skilful and judicious hands; and it is impossible not to be struck with the wonderful applicability of that instrument to the largest of created bodies as well as to the smallest, when we look at the results of Professor Owen'a discovery of the highly-organised dental structure in Labyrinth,odon, an extinct animal of a low grade, where it could hardly have been expected to occur.
The reading of Professor Owen'a memoir was accompanied by the exhibition of a diagram representing a restoration of two species of Labyrinlhodon. By the Professor's kindness, we have been enabled to give a greatly reduced copy of one of them. [See the preceding column.] The bones which appear within the outline are those which were known when the paper was read. The animal is represented as impressing its footsteps on a shore of sand, now New Red-Sandstone. There is reason for believing that this Batrachian was not smooth externally, but was protected, on certain parts at least, by bony scutella.
Specimens of the foot-prints may be seen in the British Museum and in that of the Royal College of Surgeons in London.