TRIASSIC STRATA OF CUMBERLAND AND DUMFRIES. 355 



reached, assuming this coal-field to resemble that in Ayr- 

 shire, and that the upper and middle coal-measures in this 

 district are conformable to each other. 



Mr. Gibsone has fully described the profitable part of 

 the Canobie coal-field in the memoir previously quoted ; 

 and, from his great practical knowledge of the subject, 

 his opinion no doubt is of much value, and to be relied on. 

 The point where I diflPer from him is the age of the red 

 strata seen in the Esk, between Canobie Bridge and the 

 Great Fault which brings in the profitable part of the 

 Canobie coal-field near Byreburn Foot. He, like the mining 

 engineers of the West of Scotland, classes these strata 

 containing no beds of coal as Permian, whilst I term 

 them upper coal-measures. My reasons for doing so are, 

 that in their physical characters they are more like car- 

 boniferous than Permian deposits, and that they contain 

 the Spirorbis limestone, Stigmaria ficoides, and other coal- 

 plants. In former times, these fossil organic remains alone 

 would have decided the age of the deposits ; but, in Ger- 

 many, that eminent geologist and palseontologist Dr. 

 Geinitz, in his admirable work on the Permian beds, 

 under the name of Dyas, does not hesitate to include beds 

 containing the above-named fossil organic remains occur- 

 ring in the Lower Rothliegende as belonging to the Dyas 

 —his new term for Permian. When Permian and Triassic 

 strata have been as much investigated as the coal-measures, 

 we shall know more of their plants. To my surprise, Mr. 

 Kirkham, a young geologist of Manchester, some time 

 since showed me an undoubted Sternbergia, which he ob- 

 tained from the Triassic Sandstone at Weston Point, near 

 Runcorn ; and several Calamites have been met with in the 

 water-stones of Lymm, near Warrington ; so the Triassic 

 Flora may prove to be more allied to those of the Permian 

 and carboniferous than at present supposed. 



If we are to have a division between Permian and car- 



