Much difficulty was experienced in extricating the remains uninjured, for the coal beneath had yet to be worked. The greater portion was ultimately removed in a fair state of preservation, owing to the persevering attention of William Firth, a miner whose zeal was stimulated by some knowledge of geology and in particular of coal fossils.
The shale which forms the roof of the Black-Bed Coal has long been known to collectors as a repository of interesting and well- preserved fish-remains.
The Black-Bed Coal is in the middle division of the Yorkshire Coal-field, lying about 40 yards above the Better-Bed Coal, and separated by about 220 yards from the Halifax Coals, which are the lowest workable seams. The exact horizon of important fossils is, perhaps, worth noting, though within the Coal-measures no true vertical limits of species are known to exist.
Judging from a cursory survey of several public and private collections, I am inclined to think that the remains of various interesting Carboniferous Batrachians are still unrecognized as such, and taken by their possessors for parts of fishes. When we are in a position to make a correct estimate, it will probably be found that the Batrachia of the Coal-measures are not only specifically numerous but individually abundant.
EXPLANATION OF PLATE XI.
(All the figures are of the natural size.)
Fig. 1. Part of the upper jaw with teeth of Pholiderpeton scutigerum.
Figs. 2, 3, 4, 5. Scutes from various parts of the body.
Fig. 6. Front view, and Fig. 7, side view, of a detached vertebra: a, remains of the transverse process; b, the praezygapophyses; c, the posterior face of the centrum, the inferior moiety of which is broken away.
Discussion.
Mr. Salter observed that, of both plants and mollusks, it appeared to him that there were some which were eminently characteristicof different horizons in the Coal-measures, and which were to be traced over large areas. It was possible that the same might prove to be true with regard to vertebrate animals.
Dr. Duncan called attention to the conditions of life necessary for such an animal, which could not have been in accordance with the commonly received views of the character of the Carboniferous period.
(Plate XII.)
As all who have paid attention to the Dinosauria are aware, our knowledge of the structure of the skull in these extinct reptiles is very defective. This is particularly true of Megalosaurus, of which, up to the present time, only a portion of the lower jaw has been known. I am therefore very glad to be enabled, by the kindness of
