818 SECTIONAL TRANSACTIONS.— C. 



A comparison of the U. Permian fish from Madagascar with a fauna of the 

 Rothliegende shows a similar change. 



Thus it is probable that the Permian System represents a space of time as long as 

 the Carboniferous, and it is therefore convenient to maintain it. 



Dr. R. L. Sherlock. — Ever since its foundation the existence of the Permian 

 System has been a matter of dispute. Many geologists would place the strata so 

 called in the Carboniferous, others in the Triassic System, and these opposite views 

 have resulted in the retention of the Permian. The reason for the different views is 

 that the Permian consists of a lower division normally conformable to the Carboniferous 

 and containing Palaeozoic forms of life ; and an upper division conformable to the 

 Trias and containing, besides residual forms, Mesozoic animals and plants. The 

 supporters of the Permian System believe it to contain a fauna and flora intermediate 

 in character between Palaeozoic and Mesozoic types. This is mainly due to adding 

 together the totally different lists of forms from the lower and upper divisions and so 

 arriving at a passage fauna and flora. 



The lower and upper divisions have different distributions in space and if found 

 together are often unconformable. In Britain the lower division is generally recog- 

 nised as Upper Coal Measures, while the upper division passes not only upwards but 

 laterally into Trias. ^ The Lower Permian should be added to the Carboniferous and 

 the Upper Permian to the Trias. As the Rhaetic, at least in Western Europe, is 

 separated from the Trias and closely connected with the Jurassic, it is suggested that 

 the Upper Permian (Zechstein) and Trias, with the Rhaetic taken away, form a natural 

 system which may be called the Epiric (continental) System.'^ 



In Lancashire both Lower (Collyhurst Sandstone) and Upper (Marl with Lime- 

 stones) Permian pass westward into ' Bunter ' ; in West Lancashire the Bunter 

 represents the Permian as well as the Lower Trias. 



The type of the Permian System is Russian and is continental in character. The 

 life is scanty and exceptional. It appears that, in Russia, there is a lower (Artinskian) 

 division succeeding the Carboniferous conformably, and cut off by a break from red 

 beds which are the top of the System and apparently represent the Zechstein. The 

 Artinskian may well be attached to the Carboniferous and the unconformable red 

 beds to the Trias. In Germany the lower division is divided into two very unequal 

 parts, the Lower and Upper Rothliegende. The lower part is always conformable to 

 the Carboniferous while the thin upper part is unconformable to the lower, but 

 conformable to the Zechstein, of which it is probably merely the base (as in Yorkshire). 

 Probably the division between Carboniferous and Epiric falls between the Lower and 

 Upper Rothliegende. During the Lower Rothliegende there were earth movements 

 and volcanic activity which ceased before the Upper Rothliegende and Zechstein 

 were laid down. 



In North America red beds are found in places as an addendum to the Carboniferous 

 and are followed by great earth movements. It is agreed that the Upper Permian 

 (Zechstein) is absent in North America. Dr. A. S. Romer informs me that the 

 vertebrate fauna of North America is not opposed to my classification. 



In South Africa there is an apparently unbroken succession of strata from Car- 

 boniferous to Rhaetic, and there is no positive evidence of a Permian. The Dwyka 

 ice-age was called Permian largely because of the supposed glacial deposits in the 

 British Enville Beds and these are now known to be non-glacial and probably Car- 

 boniferous. Du Toit appears to have proved definitely the Carboniferous age of the 

 glacial deposits.'^ The red beds are terminated by volcanic rocks, which, if Rhaetic, 

 as supposed, form a convenient termination to the Epiric System. The Beaufort and 

 Stormberg Series are together approximately equivalent to the Epiric. 



In Australia also the ice-age is now regarded as definitely Carboniferous. Con- 

 sequently the ice-age in India also is probably Carboniferous and not Permian as 

 usually stated. The same argument applies to the ice-age of South America. 



1 Sherlock, R. L. — Relationship of the Permian to the Trias in Nottinghamshire. 

 Q.J.G.S., Vol. Ixvii., 1911, pp. 75-117 and pi. v. 



2 A Correlation of the British Permo-Triassic Rocks. Proc. Geol. Assoc., 



Part I, Vol. xxxvii., 1926, pp. 1-72 and pis. i-ii ; Part II, Vol. xxxix., pp. 49-95 and 

 pi. iv. 



' Du Toit, A. L.— Geology of South Africa, 1926, pp. 279-280. 



