55 



The Mammalian remains enumerated by M. Buteux from this pit 

 are, Elephas primigenius, Rhinoceros tichorhinus, Cervus somo- 

 nensis ?, Cervus tarandus priscus, Ursus spelceus, Hyaena spelcea, 

 Bos primigenius, Equus adamaticus, and a Felis. It would be 

 essential to determine how these fossils are distributed which occur 

 in bed No. 2, and which in bed No. 3. This has not hitherto been 

 done. The few marine shells occur mixed indiscriminately with the 

 freshwater species, chiefly amongst the flints at the base of No. 3. 

 They are very friable and somewhat scarce. It is on the top of this 

 bed of flints that the greater number of bones are found, and also, 

 it is said, the greater number of flint-implements. The author, 

 however, only saw some long flint flakes (considered by M. de 

 Perthes as flint knives) turned out of this bed in his presence, but 

 the workmanship was not very clear or apparent ; still it was as 

 much so as in some of the so-called flint knives from the peat -beds 

 and barrows. There are specimens, however, of true implements 

 ("baches") in M. de Perthes' collection from Menchecourt ; one 

 noticed by the author was from a depth of 5, and another of 7 

 metres. This would take them out from bed No. 1, but would 

 leave it uncertain whether they came from No. 2 or No. 3. From 

 their general appearance, and traces of the matrix, the author would 

 be disposed to place them in bed No. 2, but M. de Perthes believes 

 them to be from No. 3 ; if so, it must have been in some of the sub- 

 ordinate clay seams occasionally intercalated in the white sand. 



Besides the concurrent testimony of all the workmen at the dif- 

 ferent pits, which the author after careful examination saw no 

 reason to doubt, the flint-implements ("haches") bear upon them- 

 selves internal evidence of the truth of M. de Perthes' opinion. It 

 is a peculiarity of fractured chalk flints to become deeply and per- 

 manently stained and coloured, or to be left unchanged, according to 

 the nature of the matrix in which they are imbedded. In most clay 

 beds they become outside of a bright opaque white or porcelainic ; 

 in white calcareous or siliceous sand their fractured black surfaces 

 remain almost unchanged ; whilst in beds of ochreous and ferru- 

 ginous sands, the flints are stained of the light yellow and deep brown 

 colours so well exhibited in the common ochreous gravel of the 

 neighbourhood of London. This change is the work of very long 

 time, and of moisture before the opening out of the beds. Now in 



