no Present State of the Devonian Question. [January, 



Millstone Grit series were the equivalents of those beds 

 which lie south of Barnstaple.* 



Mr. Jukes identified the culm-measures as exactly like 

 the Irish coal-measures, especially in the Kilkenny coal- 

 field. t 



From this it naturally follows that the beds beneath the 

 culm- rieasures must represent the lower carboniferous 

 rocks, and in part, at any rate, Mr. Jukes's notions must be 

 correct. He would limit the term Devonian, and retain its 

 use, for those beds containing the marine fossils commonly 

 known under the name of Devonian fossils. The old red 

 sandstone does not contain any of these fossils, and is a 

 group of rocks distinct and altogether below them. He 

 further ventured to advance the notion that the Devonian 

 beds may rather be looked upon as the most general type of 

 those which intervene between the coal-measures and the 

 old red sandstone, and that the mountain limestone is rather 

 a local and exceptional peculiarity.^ 



On the other hand, Mr. Etheridge considers that we must 

 either admit that the Devonian is a marine equivalent in 

 time of the old red sandstone, or that it must be a distinct 

 life-system, occupying an immense area, spreading over an 

 enormous interval of time between the completion of the 

 old red sandstone as a whole and the commencement of the 

 succeeding and well-marked carboniferous series. § The 

 latter opinion seems to be that generally adopted ; for in 

 remarking upon the opinions since expressed, if we do not 

 find a tendency towards the acceptance of Mr. Jukes's 

 views, we see that geologists are beginning to regard the 

 Devonian rocks as newer than the old red sandstone. 



Mr. Godwin-Austen has stated that he had always re- 

 garded the Devonian system as merely an older member of 

 the Carboniferous, holding much the same relation to it as 

 the Neocomian to the Cretaceous ; and that he would be 

 glad to see it recognised, not as an independent system, 

 but merely as the introduction of that far more important 

 system the Carboniferous, during the deposit of both of 

 which the globe presented the same physiographical con- 

 ditions. || 



Professor Phillips, too, observes that " the old red sand- 

 stone is followed in Devonshire, and still more remarkably 



* Report of Coal Commission, vol. ii., p. 421. 



f Notes, &c, p. 31. 



+ Quart. Journ. Geol. Soc, vol. xxii., p. 369. 



§ Ibid., vol. xxiii., p. 613. 



|| Ibid., vol. xxviii., 1872, p. 30. 



