JST. 47.] MENCHECOURT. 143 



On December 3rd Prestwich addressed a letter to 

 the * Athenaeum' on "Flint Implements in the Drift," 

 in reply to one through the same channel from Pro- 

 fessor Henslow, who at that time objected to our 

 geologist's conclusion that the flint implements of 

 Hoxne were in all probability found as described by 

 Mr Frere i.e., associated with the remains of the 

 mammoth, and possibly of other extinct animals, in 

 undisturbed beds of the Post-Pliocene age. 



J. Prestwich to Sir C. Lyell. 28A December 1859. 



MY DEAR SIR CHARLES, I think the report of the occurrence 

 of the greater part of the skeleton of a rhinoceros in the " Sable 

 aigu " at Menchecourt is to be depended upon. It is not, however, 

 anywhere referred to that I am aware of, unless by Dr Eavin in 

 the Mem. of the * Societe d'Emulation ' of Abbeville. I have 

 the series, but that volume is missing. I am promised it by 

 M. B. de Perthes. Nor do I recollect whether M. B. de Perthes 

 refers to it in his ' Anti[quite*s] Ante[diluviennes].' I think you 

 have the vol. containing the Menchecourt section, which I sent 

 you before you went to France. It is in the " Sable aigu " that 

 flint implements are said by M. B. de Perthes to have been 

 found, but I do not think the evidence conclusive. Still I think 

 it probable most of the 'haches' M. B. de P. showed from 

 Menchecourt had an opacity and porcelanic aspect which indi- 

 cated extraction from a light-coloured clayey matrix, and I found 

 that in the lower part of the " Sable aigu " there often is a sub- 

 ordinate seam of whitish clay. Others are stained ochreous, and 

 I found small patches of ochreous gravel in the same position. 

 Others again seemed to me, from the depth noted and their 

 colour, &c., to have come from the loess-like deposit over the 

 " Sable aigu." That the Cyrena came from " Sable aigu " I have 

 no doubt. M. Marcotte promised to collect for me during the 

 winter diggings. I shall, however, if possible, run over myself 

 for a few days. It would certainly not be safe to take the 

 hippopotamus of St Eoch as of the same set of things. I found 

 no worked flints there, nor had the present workmen ever found 



