Rev. A. Irving — On the Permian and Trias. 



273 



to a depth of about 2500 English feet." (Here is surely something 

 more than a mere appendage to the Carboniferous.) The correspond- 

 ing strata which lie to the south of the Harz Range are not of such 

 gigantic dimensions ; otherwise a similar description applies to them. 

 The sequence of things in the later Palaeozoic times has been so 

 well generalized by Credner in the form of a table that I take the 

 liberty here of transcribing it : 



5. Deep Sea. 



4. SubsidencevLoA&x 

 the sea. 



Marine 

 formations. 



Shore 

 formations. 



Limestone. 



Conglomerates 



and 



Sandstones. 



Marine 

 animal - 

 remains. 



Zeehslein ; ^ 

 Mothliegendes ; 



General Unconformity, {"■hdujige Discorclanzy). 





3. Stationary/ con- 

 dition broken by 

 insignificant os- 

 cillations. 



2. JSlevation above 

 the sea. 



1. Deep Sea. 



Freshwater and 

 marsh forma- 

 tions broken by 

 shore and 

 shallow sea 

 formations. 

 Shore forma- 

 tions. 



Marine 

 formations. 



Coal-bearing 

 strata. 



Conglomerates 



and 



Sandstones. 



Limestone. 



Land- 

 plants. 



Marine 

 animal - 

 remains. 



Coal-bearing 

 Mothliegendes J 

 and productive -. 

 Goal-measures • 



Sandstones 

 without Coal- 

 seams ; Culm ; 

 Carboniferous 

 Limestone ; 



o 



J 



The only point which seems open to question here is the use of 

 making a break between the lower coal-bearing Eothliegende and 

 the Coal-measures proper, especially as the discordancy of the strata 

 is more generally above than below them. Of course the German 

 geologists must have good reasons for this, and are no doubt con- 

 vinced that upon the whole it is required by the general facies of 

 the plant-remains which characterize these lower Eothliegende. On 

 the other hand, it would appear that such reasons ought to be very 

 strong indeed, when simplicity would suggest the grouping of them 

 with the Coal-measures. 



In the. South Staffordshire area we come across a series of sand- 

 stones and conglomerates, especially about the Licky and Clent 

 Hills, in which the counterpart of the German Eothliegende seems 

 to be met with. The best description of these is perhaps to be 

 found in the Survey Memoir of the district, before referred to, by 

 Mr. Jukes. That author estimated the thickness of the series at 

 about 1,500 feet. The included fragments, many of which are a 

 foot and a foot and a half in diameter, are derived in about equal 

 proportions from "trappean" and other rocks, many of the latter 

 being of Silurian age. The}' are unconformable to the older rocks 

 upon which they lie, inclusive of the Coal-measures. Mr. Jukes's 

 description gives us a picture of a series of deposits filling up the 

 creeks and bays of an older Palaeozoic region, and occupying a 

 position in relation to it similar to that which is occupied by the 

 Eothliegende of Germany in relation to the older rocks. 



DECADE II. — VOL. IX. — NO. TI. 



18 



