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exclusively composed 'of the great and inferior Oolite. It generally abounds 

 in fossils, the cephalopoda being especially numerous, with a great variety 

 of large pectens, pinna, and other marine shells, and in places several species 

 of star fish and Ophiura have been met with, both in the ironstone and in 

 the dark clays and shales which underlie the marlstone. Some of these 

 inferior sandy beds abound in fossils. This portion of the Lias at Shipston, in 

 Warwickshire, contains in abundance a fine species of coral, montlivaltia 

 cuneata, the largest known in our Lias, except the isasirea Murchisoni. 

 Although not noticed, yet below this horizon it occurs in the infra Liaasio 

 strata at Saint Cassian, in the Alps, and therefore must have a wide range. 

 In Gloucestershire the marlstone and associated beds attain a thickness of 

 116 feet. The underlying Ochraceous Lias,* rarely exposed, is full of 

 yellow ferruginous nodules, 4 feet, containing belemnites elongatus, trochus 

 imbricatus, cardinia attenuata, spirifer punctaius and rostratas, a>xa Buckmani, 

 mytiliis hippocampus, &o. Below this, and forming the top of the lower Lias, 

 in Gloucestershire and elsewhere, are masses of dark-coloured calcareo 

 argillaceous and finely laminated clays and shales, which may be divided into 

 separate beds, each of which is characterised by some peculiar fossils. 



Laminated Lias. — This is the uppermost clay bed of the lower Lias 

 shale, about 10 feet thick. It contains ammonites Conybeari, Henleyi, perni 

 ventricosa, pentacrinites, ophioderma, Brodiei, area truneata, gryphcea cymb'um,, 

 &c. These are succeeded by thick clays, respectively termed the belemuite and 

 ammonite beds ; the first 12 feet and the second 3 feet thick, abounding in 

 the genera named ; ammonites eJegans, Turneri, Smithii, and planicostatus, 

 and others, characterising the latter. As this stratum is of a yellow colour, 

 from the prevalence of iron, it can lithologically be easily distinguished from 

 the argillaceous stratum succeeding it, ten feet or more in thickness, named 

 the hippopodium bed, from a remarkable bivalve shell which abounds in it, 

 and also yields a variety of other testacea, viz., gryphcea incurva and obliquata, 

 terebratula numismalis, rhynchoncUa, and two small corals, a species of 

 montlivaltia, and thccocyathus rugosus, which are also frequently met with at 

 Fenny Compton and Houeybourne, in Warwickshire, in the same bed. Another 

 and inferior argillaceous band is characterised by ca'-dinia Listeri. These 

 Bub-divisions were adopted by my friend. Professor Buckman, in his work on 

 the geology of Cheltenham, published in 1845, and may hold good to a certain 

 extent in other equivalent portions of the Lias in other counties ; but, as I 

 said before, further discoveries may lead to a considerable modification of 

 these sub-divisions founded upon special fossils, which may, as I believe, 

 ultimately be found to have a much more extensive vertical range. Very few 

 fish occur in this part of the lower Lias in Gloucestershire and Warwickshire, 



* I have classed the ochraceous or yellow Lias with the marlstone, to which it 

 evidently more properly belongs. In Yorkshire the marlstoue and ironstone series are 

 abfut 160 feet thiclt. The entire thickness of the whole of the Lias in Gloucestershire 

 is probably not ranch less than 1,000 feet. At Bridpjrt, in Dorset, the middle Lias 

 amounts to a thickness of 250 feet, and the upper Lias 230 feet. 



