t)f the Environs of Paris, 51 



£lr(y ihlcrlaic! witli marie: they are but thin? and are alter- 

 iiateti wiih slratn oK inaric ; thefe are gqiieraily five such, 

 which are continued to greai distanccsi 



But tiicst: facts, which are already known, are not the 

 most important : we mention li^cui onlv thai they may be 

 brought under view at one glance. Tiie fossils which this 

 mass contains, and those coniidned in the marie that covers 

 it, present obfcrvations oF a thlTcrent interest. 



It is in this first mass that we daily find the skeletons of 

 unknown birds and of quadrupeds, which have been already 

 described by one of us (M. Cuvier) in a separate memoir'^"* 

 1\) the northward of Paris they are in the gvpsous mass 

 itself; here they have preserved their solidity, and are only 

 surrounded by a very thin stratum of calcareous marlc ; but 

 ill the quarries to the southward, they are frequently in the 

 marie which se}>aratcs the gypsous strata : they have then 

 a great de«iTce of friability. We 'shall not revert to the 

 manner in which they are situated in the mass ; upon their 

 state of preservation, species, &c. these objects having been 

 siifficientlv develoi)ed in the Memoirs wliich wc have men- 

 tioned. We have also found in this mass, bones of tortoises 

 and skeletons of fish. 



But what is much more remarkable, and much more im- 

 portant from the consequences that result from it, is, that 

 we find, althouirh very rarely, fresh-water shells. Indeed^ 

 one only is snflicient to demot^strate the truth of the opi- 

 nion of Laniitnon and some other natur;ilists, who think 

 that the gvpsums of Montmarlre, and of the other liillocks 

 of the basin of l^aris, have been crystallised in fresh- water 

 lakes.* We shall relate new facts in confirmation of this. 



\\\ the last place, the superficial mas^i is essentially eharac- 

 •te^rized by the presence of the skeletons of mammiferss. 

 These fossil bones serve to point it init where it occurs in 

 isolated masses ; for we have never been able to discover 

 that they have been found in the lower masses. 



Above the gypsum are placed strong strata of marle^ 

 sometinjcs calcareous, .-^nd sometimes aigillaeeous. 



ft is in the lower beds, and in a while and friable calca- 

 reous mass, that we have at various times met with trunks 

 of palm- trees converted into silcx. They were lying flat, 

 and of a large bulk. It is in this same system of strata that 

 we found (hut onlv at Rdujainville) shells of the genus 

 lijmiwa And pld/iorbes, v\hich seem to differ in no respect 

 from the species now existing in our marshes. One of us 

 has already comnumicated this important fact to the class. 



* V\.\b\:shed in ytunales'ru Muivufn. . 

 JD 9 



