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Notes on the distribution of the Fossil Conchologu of the Oolitit 

 Formations in the vicinity of Minchinhampton, Gloucestershire, By 

 Johx Lycett, Esq. 



Read 8th August, 1848. 



The following remarks have been written chiefly with a view to illustrate 

 the contents of the author's cabinet, premising that the objects in question 

 constitute materials fitted rather for private study than for public demon- 

 stration. The bones of gigantic Saurian reptiles, of fishes, the shells of 

 great Cephalopods, are appreciated even by the uninstructed spectator. 

 They speak to his senses of a creation distinct from that which he sees 

 around him, and he is prepared to hear of further wonders when the voice 

 of comparative anatomy tells him of their organization and consequent 

 habits. None of these fall within the scope of my remarks ; they are 

 absent: we know that they existed contemporaneously with the deposition 

 of these rocks and their included fossils : Stonesfield in this country, 

 Pappenheim and Solenhofen in Germany assure us of this. Speaking with 

 the caution which the subject demands, it may be asserted that the 

 conditions of sea-bottom in our neighbourhood, though varying consider- 

 ably during the time which was required for an accumulation of 400 feet in 

 vertical thickness of solid rock, and the creation and extinction of many 

 forms of molluscous animals, at no time constituted the estuary of a great 

 river. We search in vain for the relics of air-breathing animals and plants 

 periodically carried down and spread over its floor. The only vegetable 

 remains are fragments of wood which may have floated on the ocean wave 

 to whatever quarter the winds and currents directed them. 



With the great Saurians the case was different ; whether denizens of the 

 land, of rivers, or of estuary waters, their remains were entombed in the fine 

 mud which fluviatile waters deposit so copiously. 



We should not expect, nor do we find, a large number of marine shells 

 associated with such deposits } their paucity is perfectly compatible with 

 what we know of brackish waters of the recent period, and the small 

 number of marine species which they furnish. Precluded then from dis- 

 playing this description of fossil treasures, we revert to the less striking 

 remains of molluscous animals, and these from their number, their associa- 

 tion, their separation into distinct groups and other circumstances repeated 

 at different periods, acquire an interest distinct from that which would 

 attach to them as mere examples of fossil conchology. To illustrate there- 

 fore this portion of the subject the present memoir is chiefly directed, 

 interspersed with notices of such remarkable or characteristic forms as have 

 hitherto been imperfectly described, or which impart to these assemblages 

 their prominent and distinguishing features. 



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