ON HYPEEOBAPEEOX GOEDOXI. 



675 



47. Fuethee Obseeyations upon Hypeeoeapeeon Gordont. 

 By Prof. T. H. Huxley, F.R.S., F.G.S. (Eead May 11, 1887.) 



[Plates XXVI. & XXYII.] 



It is now twenty-nine years since, in describing those remains of 

 Stagonolepis JRobertsoni from the Elgin Sandstones which enabled 

 me to determine the reptilian nature and the crocodilian affinities 

 of that supposed fish, I indicated the occurrence in the same beds 

 of a Lacertilian reptile, to which I gave the name of Hyperodapedon 

 Gordonii I laid stress upon the " marked affinity with certain 

 Triassic reptiles " (e. g. Rliynchosaurus) of Hyperodapedon, and I 

 said that these, " when taken together with the resemblance of 

 Stagonolepis to Mesozoic Crocodilia," led me " to require the strongest 

 stratigraphical proof before admitting the Palaeozoic age of the beds 

 in which it occurs " *. 



Many Fellows of the Society will remember the prolonged dis- 

 cussions which took place, in the course of the ensuing ten or twelve 

 years, before the Mesozoic age of the reptiliferous sandstones of 

 Elgin was universally admitted. Hyperodapedon was destined to 

 play no inconsiderable part in the controversy. Some ten years 

 after the discovery of the original specimen, remains referable to 

 the same genus were found in strata of unquestionably Triassic age 

 in Central and Southern England ; and, about the same time, I 

 received abundant evidence of the occurrence of Hyperodapedon, 

 associated with Dicynodonts, Crocodilia, and Labyrinthodonts, in 

 certain Indian rocks which, on other grounds, were strongly sus- 

 pected to belong to the oldest Mesozoic series. An account of these 

 new materials, together with a full description of the original speci- 

 men of Hyperodapedon, was read before the Society and published 

 in the ' Quarterly Journal ' for 1869 f. 



Unfortunately the type specimen, now in the Elgin Museum, was 

 in very bad condition; and though, by careful study of the fossil 

 itself, it was possible to make out all the most important features 

 of the skeleton, the work of the artist employed to figure it turned 

 out so unsatisfactory, that' I abstained from publishing the two 

 plates which were prepared for the Memoirs of the Geological Survey, 

 thinking it wiser to wait until better materials should make their 

 appearance. My discretion has been justified by the event, as a 

 second specimen, of almost exactly the same dimensions as the first, 

 was discovered in the Lossiemouth Quarries, and became the pro- 

 perty of the British Museum some time ago. It has been worked 

 out with a skill which my old experience of the nature of the matrix 

 of these Elgin fossils enables me fully to appreciate, by Mr. Hall, 

 and my friend Dr. "Woodward has been so good as to place it in 

 my hands for description. 



* Quart. Journ. Geol. Soc. vol. xv. 1859, p. 460. 



t " On Hyperodapedon" Quart. Journ. Geol. Soc. 1869, vol. xxv. p. 138. 



