148 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Jan. 13, 



into the water, and that which takes to the sea habitually. All 

 that can be said is that the Lacertilia are so predominantly terres- 

 trial a group, that a member of the group is to be presumed terres- 

 trial, or at any rate fluviatile, unless evidence appears to the con- 

 trary. True there is no evidence to the contrary in the case of 

 Hyper odapedon; but, on the other hand, all that we know of its 

 contemporaries and compatriots, Stagonolepis and Telerpeton, leads 

 to the belief that they were terrestrial or semiaquatic. Telerpeton, 

 I have little doubt, was altogether terrestrial. Sphenodon, the existing 

 ally of Hyperodapedon, is a sluggish animal, which lives, in part, at 

 any rate, on insects and small birds, and is said to frequent burrows 

 in the sand near the sea-shore. The fact that no marine remains 

 have ever been found in the deposits which contain Hyperodapedon- 

 remains is negative evidence which leads in the same direction ; 

 and it is strongly confirmed by the association of Labyrinthodonts 

 with Hyperodapedon in Warwickshire and in India, — Labyrintho- 

 donts, like all other amphibia, being confined to the land and fresh 

 water. 



The question of the terrestrial habit of Hyperodapedon assumes a 

 great importance when the wide distribution of the genus is taken 

 into consideration. It has now been discovered in the JN^orth of 

 Scotland, in the centre of England, and in Central India ; and if it 

 were, as I doubt not it was, a terrestrial or semiterrestrial animal, 

 that alone indicates the existence of a very extended mass of dry land 

 in the Northern hemisphere during the period in which it lived. 

 And the proof of the existence of continental land in the Northern 

 liemisphere acquires increased interest when we consider the evi- 

 dence which shows what period this was. 



The cardinal fact in that evidence is the occurrence of Hyperoda- 

 pedon in the Coton-End Quarry in Warwickshire, as proved by Dr. 

 Lloyd's specimen. It has never been doubted, I believe, that the 

 Sandstone in which this quarry is excavated is of Triassic age. It 

 has yielded Labyrinthodonts and Thecodont Saurians ; and its strati- 

 graphical position is such that the only question which can possibly 

 arise is, whether it is Triassic or Permian. 



As next in order of value, I take the discovery of Hyperodapedon 

 in the Devonshire Sandstone, the determination of which as Trias 

 rests, as Mr. Whitaker will inform you, upon independent grounds. 



Thirdly comes the occurrence of the closely allied Rhynchosaurus 

 in the Trias of Shropshire — a fact of subordinate value, but still by 

 no means to be left out of sight. 



These facts leave no possible doubt, as it seems to me, that Hype- 

 rodapedon is a reptile of Triassic age ; but whether it is of exclu- 

 sively Triassic age or not, and therefore whether it is, or is not, 

 competent to serve as a mark of the Triassic age of the deposit in 

 which it occurs, is quite another matter, and one respecting which 

 it behoves us to speak very cautiously. 



Crocodiles, with the same vertebral character as those which now 

 live, and not known to be distinct even from the modern restricted 

 genus Crocodilus, lived at the epoch of the Greensand, or, in other 



