CARBONIFEROUS LIMESTONE OF LILLESHALL. 



107 



rise again with an inclination to the south-east, the flexure being caused by the line of disturbance 

 which proceeds from near Steeraway to Lilleshall, and along which indeed there are traces of the 

 limestone being upcast, accompanied at one spot (the bottom of Hadley inclined plane) by a knoll 

 of trap. (See Map.) On the north-eastern and northern face of the trap rock of Lilleshall Hill, 

 the carboniferous limestone is again brought up, and appears on the sides of the roads and in some 

 old works extending to the high road from Wellington to Newport. It here folds over, or rather is 

 broken up by an anticlinal line proceeding from the trap rock, and by which the limestone itself is 

 thrown into a saddle, dipping both to the east and west. The prevailing dip, however, is to the 

 east- north-east, by which inclination the lime rock is carried rapidly underground, disappearing 

 beneath certain white and red carbonaceous sandstones with impressions of coal plants. 



The limestone of Lilleshall is extracted by shafts upon the dip to a distance of more 

 than a mile from its outcrop with a prevailing easterly dip ; the deepest shafts (those 

 near the village of Aston) being one hundred and twenty yards. The succession of most 

 of the limestone beds can, however, be best studied in the old open works near the 

 basset. The following is the section, in descending order, of all the strata. 



1. Red sandstone, a good freestone, with impressions of coal plants. This rock, which is traversed by the new shafts, is 

 a variety of the millstone grit, similar to that which will hereafter be described at Sweeny near Oswestry, and at Cromhall 

 near Tortworth, Gloucestershire. (Upper limestone shale of Conybeare and Buckland.) 



2. Sandstones of purplish pink and white colours, with a few impressions of stems of plants. Thirty to forty feet of this 

 rock are seen at the old open works. These pass down into a very thin flaglike fine-grained sandy limestone, spotted with 

 dark grains of brown oxide of iron ; there are also a few small geodes of iron as large as apricots. 



c. Yellow and red shale. 



d. Grum. Dull dark red and green impure concretionary limestone, in parts ferruginous, each geode being enveloped in 



red shale. The Productus hemisphcericus and another species are most abundant, together with the corals Litho- 

 strotion floriforme (Fleming), Syringopora reticulata (Goldfuss), and Lithodendron irregidare (Phillips) (Cladocora, 

 of Ehrenberg). This mass is about twenty feet thick. 



e. Flat-bedded greyish-green limestone of about a foot in thickness. 

 /. Partial wayboards of red and black shale. 



Observing the organic remains in this portion of the quarry, I was struck with the 

 regularity of their arrangement, but especially in the case of the large coral Lithostrotion 

 (Lhwydd), L. floriforme (Fleming), represented in the above wood-cut 1 . 



This coral y, y was two feet five inches wide, by one and a half feet in height. The 



1 From the position of the coral represented in this wood-cut, the generic and specific characters cannot 

 be distinguished. The coral was first determined by Lhywdd as early as the year 1699, and has subsequently 

 received the following names from other naturalists. Erismatolithus madreporites (Floriformis) Martin. Pet. 



