LOWER LIAS. 269 



Ammoniles capricormis are worked for brickmaking.^ (See Fig. 42.) 

 On the top of the Lower Lias in north-west Lincolnshire there is 

 a Pecten-bed with P. Icevis, which marks the junction with the 

 Middle Lias. 



The Lower Lias is exposed in places on the coast of Yorkshire, 

 between Redcar and Staithes or Colburn Nab, and in Robin Hood 

 Bay. The following divisions have been made : ^ — 



Zones. Feet 



A. ca/ncormts.— Shales, sandy and micaceous towards the upper part, 

 with A. finihrialtis, A. HeiiLyi, A. Bcchci, etc. Robin 

 Hood's Bay, RockcHff, HuntcHff, and Coatham Scars 150 



A. yrtw/^^^/w' (inchiding zone of A. annaliis). — Micaceous and sandy shales 

 with 'doggers' of ferro-argillaceous limestone. A. bre-oi- 

 spuia, A. Henleyi, A, Loscombi, A. fimbriatus, etc. Robin 

 Hood's Bay 220 



A. oxynoins. — Shales and indurated marls. A. cbtusits, A. raricostatiis, A. 



stellaris, A. semicostatiis, etc. Robin Hood's Bay IIO 



A. Bucklandi. — Shales with thin earthy and shelly limestones. A. Turiieri, 

 A. Brooki, A. Birchii, A. semicostatiis, A. multicostatiis, 

 Hippopodium ponderosum. Redcar 180 



A. angidatits. — Thin rubbly and earthy limestones, including Cardinia- 

 shale with C. ovalis, Hippopodium ponderosum. Near 

 Market Weighton and Redcar tp 



A. planorbis. — Clays with thin limestones. North Cliff, near Market 



Weighton 50 



Lower Lias has also been recognized at Frees in Shropshire, and 

 at Audlem in Cheshire, over a tract of ground between the Hawk- 

 stone Hills, Whitchurch, and Market Drayton. The beds are much 

 obscured by Drifts, but where exposed they have led to trials for 

 coal. Ammo7iites planorbis, A. Cojiybeari, A. Bucklandi, and GryphcEa 

 inciirva have been recorded.^ It has been suggested that traces of 

 Lias may occur beneath the estuary of the Ribble, being preserved 

 in a synclinal above the Keuper Marls, etc.* 



In Cumberland, west of Carlisle, there is about 120 feet of dark 

 shales and limestone (including, perhaps, the Rhsetic Beds), in 

 which the Rev. F. B. Brodie identified the Lima and Saurian Beds. 

 The strata are much hidden by Drift, but they are exposed at 

 Quarry-Gill, and one or two places between Aikton and Great 

 Orton. They were first observed by Mr. R. B. Brockbank.^ 



Ecojioviic products, etc., of the Lower Lias. 



Ironstone has been profitably worked in Lincolnshire, and it was formerly 

 worked in the upper beds of the Lower Lias at Robinswood Hill, near Gloucester, 



1 W. D. Carr, G. Mag. 1883, p. 164. See also Geol. S. W. Lincolnshire 

 (Geol. Survey), by A. J. Jukes-Browne and W. H. Dalton. 



- Tate and Blake, Yorkshire Lias ; Explan. Sheets 93 N.E. 95 N.W. and 96 

 N.E. (Geol. Survey), by C. F. Strangways, C. Reid, and G. Barrow ; M. 

 Simpson, Guide to the Geology of the Yorkshire Coast, edit. 4 ; J. F. Blake, 

 Q.J. xxviii. 132. 



2 Murchison, Proc. G. S. ii. 1 1 5, and Silurian System, p. 23. 

 * C. E. De Ranee, G. Mag. 1883, p. 505. 



6 E. W. Binney, Q. J. xv. 549 ; T. V, Holmes, Q. J. xxxvii. 293 ; and P. GeoL 

 Assoc, vii. 418. 



