TRIASSIC STRATA OF CUMBERLAND AND DUMFRIES. 347 



valuable coal-field; but there is also atCanobie a great thick- 

 ness of upper coal-measures, containing a seam of limestone 

 in all respects like the Ballochmoyle Braes, near Catrine, 

 the Ardwick, and Leebotwood limestones. Consequently 

 the Permian fault should be called by some other name ; 

 say, the Great South fault. Practical mining engineers have 

 frequently classed all the red and variegated beds vrhich they 

 find in the upper part of the coal-measures as ^' red mea- 

 sures^' or Permian strata. Now there is, no doubt, often 

 great difficulty in drawing the line of demarcation between 

 the upper coal-measures and the Permian strata ; and it is 

 possible that in some sections one may pass into the other, 

 as appears to be the case in the river section above the 

 bridge at Canobie previously alluded to j but in the north- 

 west of England this transition is not generally to be seen. 

 The further we investigate the organic remains of these two 

 formations, probably more genera and species will be found 

 to be common to both than is at present supposed , but in 

 all cases where the remains of Stigmaria and Spirorbis 

 carbonarius {Micro conchus) have been found in the strata, 

 I have termed them carboniferous. In the absence of 

 organic remains, which is generally the rule, and not the 

 exception, the Permian character of the strata has been 

 decided by the mechanical character of the deposits and 

 the order of superposition, the beds of breccia and the soft 

 red sandstone generally .affording pretty good evidence of 

 the Permian age of the strata over a great extent of country, 

 and varying with the character of the older rocks found in 

 situ in the district. If the Permian beds are taken as the 

 Moat sandstone, the red shales with gypsum and magnesian 

 limestone and breccias lying in soft red sandstone at Can- 

 obie, their identification is pretty easy ; but in continuing 

 them downwards into the upper coal-measures, or in tracing 

 their boundary upwards into the Trias, there is greater 

 difficulty, as good natural sections, showing the passage of 



