AND TRIAS OF CENTRAL EUROPE, 403 
As for the word ‘“‘ Dyas,” if it meant (as asserted) the occurrence of 
two sets of strata, terrestrial and marine, it was applicable to many 
formations. Further, the asserted pre-Triassic denudation of the 
Zechstein may have removed strata enough to have constituted it 
once a Trias or even a Tesseras. The local absence of the upper- 
most portion of a formation allows the Lias, for instance, the Oolite, 
Chalk, Hocene, &c., to be found perfect only here and there; and the 
existence of any supra-Zechstein Permian sandstone anywhere 
negatives the general adaptability of the word “ Dyas.” The speaker 
eriticized one of the illustrative diagrams, and pointed out that, with 
Mr. Irving’s explanation of Prof. Geinitz’s second aspect of Dyas, 
namely the duality or lateral parallelism of strata, we should have to 
regard nearly all limited, lenticular, intercalated beds as “ Dyadic.” 
Mr. Torrey did not think the evidence adduced was sufficient to 
prove the unconformities insisted upon. The facts shown in the 
sections exhibited could be explained by chemical erosion. 
Mr. Branrorp doubted whether several of the sections brought 
forward by the author had been rightly interpreted. He agreed with 
the last speaker that some of the sections adduced look like subter- 
ranean removal of a calcareous rock by water containing carbonic 
acid. He thought the name Permian, as being the older, ought to 
stand, but that Permian was merely Upper Carboniferous. 
Prof. M‘Krnny Hveuss was in favour of retaining the old name 
“New Red” for both Permian and Trias of Britain. He considered 
that in this case the physical evidence was of more importance than 
the paleontological, especially as fossils were rare in both the lower 
and upper divisions. He criticized the fossil evidence, pointing out 
that new types came in with the Magnesian-limestone series: Schi- 
zodus, for instance, he looked upon as the forerunner of Trigonia. 
Though old forms, as Producta, lingered on, no one would draw the 
upper boundary of the Magnesian Limestone exactly where that 
fossil ceased to occur, while on the Continent Paleeozoic types ran on 
into the Trias. If there were beds in other countries more closely 
allied, on both kinds of evidence, to the Carboniferous, by all means 
put them with the Carboniferous; but the Magnesian-limestone 
series of Britain could not on any evidence be bracketed with the 
Coal-measures. 
Principal Dawson stated that in Nova Scotia and Prince Edward 
Island there was a gradual passage upward from the Upper Coal- 
formation to the Permian or Permo-Carboniferous, but that there 
seemed to be discordance between the latter and the Trias, though 
the two formations resembled each other in mineral character. 
The AutHor disclaimed any idea of slighting the work or memory 
of Murchison. He did not regard the question as merely one of 
terms. Prof. Hull had admitted that Murchison’s classification was 
indefensible. He insisted that geographical names are not the best 
for geological systems. He admitted that the Permian was an upward 
extension of the Carboniferous. He could not agree that subterra- 
nean erosion would account for the sections described. The facts 
brought forward indicated a considerable interval in time between 
the Dyas and Trias. 
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