CHAP. IX. BASIN OF THE SEINE. 151 



to a foot or more in diameter. These blocks are peculiarly 

 abundant in the lower drift commonly called the ' diluvium 

 The granitic materials are traceable to a chain of hills 

 called the Morvan, where the head waters of the Yonne take 

 their rise, 150 miles to the SSE. of Paris. 



It was in this lowest gravel that M. H. T. Grosse, of Geneva, 

 found, in April 1860, in the suburbs of Paris, at La Motte 

 Piquet, on the left bank of the Seine, one or two well- 

 formed flint implements of the Amiens type, accompanied 

 by a great number of ruder tools or attempts at tools. I 

 visited the spot in 1861 with M. Hebert, and saw the stratum 

 from which the worked flints had been extracted, twenty feet 

 below the surface, and near the bottom of the 'grey dilu 

 vium,' a bed of gravel from which I have myself, in and 

 near Paris, frequently collected the bones of the elephant, 

 horse, and other mammalia. 



More recently, M. Lartet has discovered at Clichy, in the 

 environs of Paris, in the same lower gravel, a well-shaped 

 flint implement of the Amiens type, together with remains 

 both of Elephas primigenius and E. antiquus. No tools 

 have yet been met with in any of the gravel occurring at the 

 higher levels of the valley of the Seine ; but no importance 

 can be attached to this negative fact, as so little search has 

 yet been made for them. 



Mr. Prestwich has observed contortions indicative of ice- 

 action, of the same kind as those near Amiens (see p. 138), 

 in the higher level drift at Charonne, near Paris ; but as yet 

 no similar derangement has been seen in the lower gravels a 

 fact, so far as it goes, in unison with the phenomena observed 

 in Picardy. 



In the cavern of Arcy-sur- Yonne a series of deposits have 

 lately been investigated by the Marquis de Vibraye, who 

 discovered human bones in the lowest of them, mixed with 

 remains of quadrupeds of extinct and recent species. This 



