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 A HISTORY OF RUTLAND formed in close proximity to land, probably in the estuary of a large river or in lagoons adjoining such an estuary. THE LINCOLNSHIRE LIMESTONE This formation has received its name from the fact of its being most fully developed in Lincolnshire, and though it extends southward through Rutland and part of Northamptonshire it becomes rapidly thinner to the southward and finally disappears near Kettering and Maidwell. It is believed to represent the upper part of the Inferior Oolite of Gloucester- shire. There is a complete passage from the Northampton Sands to the Lincolnshire limestone, and the passage-beds consist of sandy and shaly limestones which have been used for roofing-slates and are known as ' Collyweston Slate ' from the village of that name south-west of Stam- ford. These beds are from 2 to lofeet thick and exhibit on the surfaces ripple-markings, worm-tracks and plant-remains, clear indications of their having been deposited in shallow water, but that this was the water of the open sea is proved by the purely marine fossils which they contain ; among these may be mentioned the Gasteropods Malaptera Betitleyi and Nat'ica cincta, with the bivalves Gervillia acuta, Pecten lens, Lucina IVrighti and 'Trigonia impressa. These passage-beds are succeeded by shelly limestones and oolitic freestones, which have a thickness of about 80 feet near Stamford and have been quarried in many places for building-stone. They exhibit various tints of yellow, grey and brown, and contain a great variety of fossils. The shelly limestones are indeed entirely composed of small shells and broken fragments of shells with broken spines and plates of Echinoidea (sea-urchins) and the joints of Crinoidea (sea-lilies). In these beds the univalve shells (Gasteropoda) are generally water-worn, and the bivalve shells are single valves, often rolled or broken ; hence it is inferred that the beds are banks of dead shells, drifted and brought together by the action of currents on the sea floor. Other beds are largely or entirely composed of small oolitic grains ; these form some of the best freestones, and do not contain many fossils, except those of very small size. There is still a third variety of rock called by Professor Judd the ' coralline facies,' which is a marly limestone, compact or but slightly oolitic in texture and abounding in corals. Some of these beds appear to have been actually parts of coral reefs, and have yielded corals belonging to the genera Isastrcea, 'Thamnastroea, Thecosmilia and Latimceandra, as well as many Brachiopoda and Mollusca, such as T'erebratula maxillata. Pinna cuneata, Modiola soiverbyana, Ceromya bajociana, Pholadomya Jidkula with species of Natica and Ner'moea. Cephalopoda are rare, but A. Murchisona, A. Blagdeni and A. subradiatus have been recorded. In referring to the accompanying map, and to that of the Geological Survey (sheet 64), from which it is reduced, it must always be remem-