430 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Apr. 4, 



consisting of limestone and schists, was of the same age as those 

 strata to which we had then just assigned the name Devonian ; and 

 the beUef was expressed that, whilst certain shelly sandstones (Ram- 

 melsberg near Goslar) probably stood in the place of the uppermost 

 Silurian, the rocks occupying the south-eastern portion of these 

 mountains, and in which at that time a very few imperfect Trilo bites 

 only had been found, would prove to be among the oldest in the chain. 



Though it formed no part of that earlier sketch to describe the 

 secondary deposits which range along the northern flank of the ridge, 

 still, as on two different occasions the authors had cast a rapid 

 general glance over them, they indicated some of their chief dislo- 

 cations and remarkable inversions of order. They also treated of the 

 probable periods at which the granite of the Brocken and other 

 igneous rocks around that mountain had been erupted. 



At that time, however, the *' Zechstein " was classed with the 

 Secondary rocks, and not grouped, as it has since been, with the 

 " Rothe-todte-liegende," so as to constitute that which one of us 

 has since termed " Permian." 



A notice like the present, which is brought before the Geological 

 Society after an interval of fifteen years, must necessarily indicate 

 other features and new bases of classification, the result of recent 

 researches and comparisons. At the same time, it is due to Prof. 

 Sedgwick and his coadjutor to state, that their views regarding the 

 "Culm" strata and the underlying Devonian limestones and schists, 

 as well as their opinion that the south-eastern portions of the Harz 

 were older than the western limits, have all proved to be correct. 

 In short, the general order of superposition of the strata, since called 

 *' palaeozoic," which was then indicated, is accurate. The only 

 changes made are palseontological, not stratigraphical, and consist in 

 the application to the Harz of that portion of the classification by 

 organic remains, established in the Rhenish provinces by Ferdinand 

 Roemer and the brothers Sandberger, whereby the sandstone charged 

 with large "Spirifers" has been abstracted from the Upper Silurian 

 of the original sketch alluded to and classed as " Lower Devonian," 

 a change, which has, indeed, been long ago adopted by ourselves and 

 all geologists. 



In the present communication we shall therefore in the first 

 instance simply attempt to give a general sketch and fill up some 

 lacunse of detail in the distribution of the palaeozoic rocks of the 

 Harz ; leaving it to native geologists to complete what is still want- 

 ing, a full illustration of this convulsed, mineralized and metamor- 

 phosed region, — a task which, however difficult of accomplishment, 

 has been commenced by M. Adolf Roemer, by the publication of a 

 geological map. 



General view of the order in which the Palceozoic Rocks succeed 

 each other in the Harz. — In a tract so perforated by igneous rocks 

 of various characters, and where, as we approach the chief axis, or 

 that of the Brocken, even the carboniferous or culm rocks are often 

 in a crystalline condition and in inverted positions, it is hopeless to 



