FOSSIL REPTILES. 277 



them than in the species between which and the fossil emys in 

 question we have instituted a comparison. 



It is said that many other emydes, or fresh-water tortoises, 

 are found in diluvial formations with the bones of elephants, 

 &c. ; but nothing satisfactory is ascertained concerning them. 



The remains of sea-tortoises, turtles, or Chelonian reptiles, 

 are found in the neighbourhood of Maestricht, in celebrated 

 quarries of a sort of coarse and sandy chalk in the mountain 

 of St. Pierre. They are mixed with marine productions of 

 many kinds, and with bones of a gigantic reptile of the 

 Saurian order. Some incomplete portions of the upper testa, 

 or carapace, were found here, which M. St. Fond, in his 

 " History of the Mountain of St. Pierre," thus speaks of: — 



*' The upper part, towards the top, bears a sufficient re- 

 semblance to a military cuirass, provided with a fore-arm, and 

 indicates that the fore-paws were partly covered with scales 

 adhering to the buckler. This constitutes a marked character, 

 from which a distinct genus might be formed, as nothing of 

 the kind occurs in any of the living species of tortoise." 



This opinion, however, of M. St. Fond is totally without foun- 

 dation. There is nothing extraordinary in these pretended fore- 

 arms, nor any thing which is not found in all the sea-tortoises, 

 and those of the land and fresh-water, the trionyx alone 

 excepted. This is easily proved by a comparison of these 

 fossil carapaces with such as have been deprived of their 

 scales, and reduced to merely their osseous frame- work, and 

 not by a comparison with those which are still covered by 

 their exterior envelope. What M. St. Fond calls the fore- 

 arm, is only the commencement of the edge which surrounds 

 the carapace, and which is usually formed by twenty-four 

 osseous pieces : only two or three of these pieces remained in 

 the specimen of which we have been speaking, the others 

 having fallen. The emargination which separates this com- 

 mencement of the edge from the disk of the carapace, is pro- 

 duced by the unossified space which remains in the tortoises 



