ANNIVERSARY ADDRESS OF THE PRESIDENT. lxv 



three distinct portions by the Anthraeitiferous formation : on the 

 South-east it occupies the whole region of the Ardennes, and is there 

 covered only by its own debris, except in one locality, where a small 

 band of the " Penean" (the Permian of our nomenclature) comes to the 

 surface ; at the North-east it is almost entirely covered by second- 

 ary strata, whilst in the centre of the great Anthracite-basin it 

 occurs in discontinuous bands parallel to the lateral edges, which 

 have thus been lifted up like islands in the centre of the great de- 

 pression. Had this elevation been carried sufficiently far, the An- 

 thraeitiferous formation would have been divided into two parts ; 

 but it has stopped short of a complete separation, the lower quartz- 

 slate of the Anthraeitiferous formation covering it in many places, 

 though the limestone immediately above the quartz-slate is completely 

 divided into two principal basins by the quartz-slate. In the Ar- 

 dennes alone is the lower system of the Slate -formation found, and 

 it there forms a single band, whilst the upper system occurs as two 

 bands, one to the north and the other to the south of the lower 

 system. It is unnecessary here to follow JUL. Dumont in his very 

 careful and able examination of the mineral character and products 

 of these rocks ; but it may be said that the symmetrical arrangement 

 of the rocks forming the lower system, in the following order from 

 below upwards — Diallage-slate, Bed Slate, Common Slate, Talcose 

 Puddingstone — on each side of an anticlinal axis, proves that the 

 lower system here forms a saddle-shaped elevation, just as the upper 

 system appears to do in the centre of the basin, with this difference, 

 however, that it is not covered, as the upper system partially is, by 

 the next series in regular order of superposition. Passing over the 

 local descriptions of the Slate-formations, the Anthraeitiferous form- 

 ation is next in order, and is divided by M. Dumont into four sys- 

 tems, namely : 1st, Slate, Sandstone, and Conglomerate, called the 

 Lower Quartz-slate ; 2nd, Limestone and Dolomite, called the Lower 

 Limestone ; 3rd, Slate and Sandstone, called the Upper Quartz-slate ; 

 4th, Limestone and Dolomite, called the Upper Limestone : and in 

 both the limestone- divisions the Dolomite occurs, though not always 

 present, between two beds of common limestone. M. Dumont, in his 

 remarks upon the order of superposition of these rocks, states that the 

 lower quartz-slate-system graduates, at its junction with the slate- 

 system of the Ardennes, so imperceptibly into the slates, that it is 

 scarcely possible to mark distinctly the line of separation, and he 

 refers this system to our Old Eed Sandstone ; but he does not in this 

 Essay effect a correlation of the three remaining systems of the An- 

 thraeitiferous formation with English formations, nor do I think that 

 the list of fossils he gives would alone have enabled a geologist to 

 decide on the true position of the Anthraeitiferous and Coal formations 

 of Liege ; as, for example, in the fossils of the Lower Quartz-schist 

 appear the names Productus hemisphcericus, P. comoides, P. concinnus, 

 and, in the Upper Limestone System thereof, Oalymene Tristani, 0. 

 macrophihalma, whilst in like manner Spirifer attenuatus is recorded 

 as occurring in the Upper Quartz-schist below the Coal-field, and in the 

 Penean or Permian formation above it I do not mention these paleeon- 

 tological obscurities with an intention to detract from the great 



