394 



Prof. J. VV. Judd. 



[Dec. 10 r 



IV. " On the Relation of the Reptiliferous Sandstone of Elgin 

 to the Upper Old Bed Sandstone." By Professor John W. 

 Judd, F.R.S., Sec. G.S. Received November 19, 1885. 



The question of the geological age of the yellow sandstones of the 

 district lying to the north of the city of Elgin has been, as is well 

 known, the subject of very animated discussions among geologists. 

 Some have even gone so far as to assert that the evidence on the 

 question, which has been adduced by palaeontologists, is absolutely 

 incapable of reconciliation with that relied upon by stratigraphists. 



Until the discovery of fossils in the beds in question, it was quite 

 natural to suppose that these white and yellow sandstones, which 

 locally assume reddish tints, are part and parcel of the Upper Old 

 Red Sandstone — a formation presenting somewhat similar mineral 

 characters, and covering a considerable area in the district. This 

 was the view which was taken by Murchison and Sedgwick, Dr. Mal- 

 colmson, Dr. Gordon, Mr. A. Robertson of Inverugie, Captain Brick- 

 enden, Mr. Patrick Duff, Mr. Martin, and indeed of all the geologists 

 who at first studied the relations of the rocks in Morayshire. 



But when fossils, which proved to be of great interest and impor- 

 tance both to the geologist and the biologist, were detected in this 

 formation, a careful re- examination of the evidence relied upon by 

 these geological pioneers was called for. The nature of these remark- 

 able fossils was indeed calculated to awaken the gravest doabt as to- 

 the correctness of the commonly received opinions concerning the 

 position in the geological series of the strata which yielded them. 



In 1844 Mr. Patrick Duff obtained from the quarries at Lossie- 

 mouth, near Elgin, a cast of portion of the dermal covering of an 

 organism of considerable size. Drawings of this fossil were sent by 

 Mr. A. Robertson, of Inverugie, to Agassiz, and were by that natu- 

 ralist described under the name of Stagonolepis Robertsoni* Agassiz 

 regarded the fossil as the impression of the scales of a ganoid fish allied 

 to MegalichtJiys and Glyptopomus. Six years later, in 1850, Captain 

 Brickenden obtained, from quarries in the same rock, at Cummings- 

 town, a series of remarkable footprints, which were believed by most 

 palaeontologists to indicate the existence of reptiles at the time when 

 the beds were deposited ; and in the following year Mr. Patrick Duff 

 obtained from the Spynie quarries the skeleton of a small Lacertilian r 

 which was described by Mantell under the name of Telerpeton 

 Elginense.f Shortly after this, many more footprints were detected 



* " Monographic des Poissons Fossiles du Vieux Gres Rouge, &c." (1844-5) r 

 p. 139. 



f "Quart. Journ. Geol. Soc," vol. viii (1852), p. 97. 



