324 SECTIONAL TRANSACTIONS.— C. 



changes, so that a natural base is provided for a new System, with a flora of more 

 Mesozoic aspect. In the marginal tract of the Urals the Saalian phase may be 

 recognised by strand-line changes in the Kungur Beds which are followed by the 

 transgressive Kazan Beds. The Artinskian would thus be placed in the Carboniferous, 

 and D. White's discovery of Autunian plants with Artinskian mollusca strengthens 

 this allocation. Correlation with the marine facies can be made via the Kazan Beds. 



A fiu-ther episode of movement (the Pfalzian or Ealatine) occurred after the Upper 

 Permian, and where this occurs, a natural boundary between Permian and Trias. 

 This is found in the Urals, Donetz Basin, Vosges, Pyrenees, Northern England, but 

 is everywhere weak. In England it was accompanied by important changes in 

 drainage direction, and for such changes some interval of time must be allowed. 

 Such a weak movement is unlikely to have produced marked strand-line changes, 

 but it is noteworthy that the base of the Marine Trias is marked by a sudden incoming 

 of new elements in the fauna. The Anisian division of the Marine Trias is correlated 

 with the Muschelkalk, and the Scythian division with (at least) the uppermost Bunter. 

 According to Stille, the oscillations in the continental area of Germanj' maj- be 

 correlated with transgressions and regressions in the Tethyan province. It seems 

 probable that the accepted base of the Marine Trias is roughly equivalent in time to 

 that of the Continental Trias. 



The Permian System is thus re- defined to include only Upper Rothliegende and 

 Zechstein (Saxonian and Thuringian). 



Prof. P. F. Kendall, F.R.S. — While there appears to be no unconformity between 

 Permian and Trias, sections in East Lancashire and Cheshire afford clear proof of a 

 formidable inter-Permian unconformity. Borings at Stockport show a conglomerate 

 which rests on various members of the Stockport Marls and Sandstone and even on 

 the Collyhurst Sandstone. This conglomerate has been shown by Dr. Versey to 

 comprise a suite of rocks including types suggesting derivation from the Wrekin- 

 Caradoc area. Close comparison may be drawn between this conglomerate and that 

 discovered in the Middle Permian Marls at Harworth, near Doncaster, which also 

 contains a large proportion of Pre-Cambrian rocks of Uriconian or Charnian types. 

 It seems likely that these two conglomerates are the records of some uplift or physio- 

 graphical change that took place after the deposition of the Lower Magnesian Limestone 

 and Middle Marl. If the two conglomerates are identical in age, it would bring 

 the Western succession into parallelism with the Eastern and would further render 

 Dr. Sherlock's correlation superfluous. 



Dr. E. Neaveeson. — Whatever controversies may rage around the British strata, 

 hitherto referred to as the Permian System, everyone is agreed that these rocks 

 (together with those of N.W. Europe generally) are of unusual type. 



As a matter of general principle, correlation within the present stratigraphical 

 classificati6n is made by means of the marine invertebrate faunas, which, being 

 most uniform and widespread, have become the standard of reference for the Systems, 

 even where the latter were first defined by non-marine faunas and floras. It can 

 safely be said that if vertebrate or plant assemblages had been taken as the basis 

 of stratigraphical subdivision throughout the geological column, a verj^ different 

 classification would have resulted. Hence, the grouping must be made on a con- 

 sistent plan if confusion is to be avoided, and the Permian System should be redefined 

 in the first instance by means of the marine invertebrate faunas which are known 

 chiefly from Sicily, India, Timor and Texas. 



The fossil assemblages from these places are sufficiently distinct from those of the 

 Carboniferous and Triassic Systems to justify the retention of the ' Permian System.' 

 For example, the ammonoids first exhibit, predominately, the frilling of the sutural 

 lobes, and many genera are restricted to Permian rocks. Moreover, the evolution of 

 the faunas and the thickness of the strata in some places necessitate such sub- 

 divisions as would make the contiguous systems unwieldy, if the Permian rocks were 

 added to either, or even divided between the two. 



In the case of Tertiary strata which yield only land-vertebrates, the rocks have 

 been fitted with considerable success into the classification based on marine faunas, 

 and there seems to be no adequate reason why the Permian continental deposits 

 should not eventually be similarly adjusted. 



The established name ' Permian ' may well be retained. Compound terms like 

 ' Permo-Carboniferous ' and ' Permo-Trias,' do not help, but only create confusion. 

 The term ' Epiric,' recently proposed for the combined Upper Permian and Trias, is 



