SECTIONS AT ABBEVILLE. 
285 
The gravelly clay h becomes more persistent and thicker as it slopes down into the 
valley. The loam c, on the contrary, is cut off gradually by and thins out : its maxi- 
mum thickness is from 25 to 28 feet. The sand d varies from 2 to 8 feet, and is thickest 
about the middle of the pit. The gravel e is of a nearly uniform thickness of ^ to 1 foot ; 
it apparently does not range up to the chalk, which, at the end of M. Dufour’s pit, has 
been met with directly under the sand d. Of the marl f I examined but few sections, 
as the diggings do not go deeper than e : it appears to be rather local. The gravel g 
w'as reached only in the trench opened in pit fig. 1. On the opposite side of the road 
to pit fig. 2, a well was dug through 25 feet of gravel and sand, but no exact particulars 
of it were kept. A few yards beyond this the gravel passes under the great mass of silt 
and peat filling the valley of the Somme. In the other direction {i. e. up the hill) the 
chalk comes to the surface at the distance of a few yards beyond and above the pits ; 
but whether it forms a cliff against which the pleistocene beds abut, or whether it 
passes by a rapid slope under them, there is no evidence to show. 
I have given a general theoretical section of the Menchecourt deposit across M. Du- 
four’s pit*, showing its relation to the valley and to the later deposits, in Section 1. 
Plate X. (See also Appendix G.) 
Organic Bemains. — Xone have been found in the upper clay and rubble, h, V \ nor 
could I find or hear of any worked flints having ever been met with in them. 
The loam c contains a few mammalian remains f. The only specimens, however, 
that I have collected, or at present know of, are the teeth of Horse and bones of rumi- 
nants and of Elephant, all much decomposed. Some flint-implements are recorded 
from this bed. I found in it shells belonging to the few following land species - 
Clausilia nigricans^ Mat. \ Helix hispida, Linn. 
Helix arhustorum, Linn. 1 Pupa muscorum, Linn. 
Of these the Helix and Pupa are common, and the Clausilia very rare. For a list of the 
extraneous microscopic fossils of this and the other beds, see Appendix (E). 
It is, however, to the sands and gravels d and e, which may be considered as one bed, 
that the greatest interest attaches, on account of the flint-implements which are found in 
them, and of the abundance of mammalian remains, with land, freshwater, and marine 
shells. The bones mostly occur in or on the seam of flint-gravel, e : they are often 
entire, but the bulk are in fragments. The land and freshwater shells are most abundant 
in the sand d ; while the marine shells are more common in the gravel e, although a 
few are scattered through d. The following list of organic remains is taken from the 
* See also the section and description of this pit in Antiq. Celt, et Anted, vol. i. p. 232-5. 
t In the accounts hitherto published of the organic remains from Menchecourt, no mention is made of 
those from this bed, or rather no distinction is made between those which come out of this bed and those 
from the strata beneath it. It is possible that some of the mammalia enumerated from d and e may also 
have been found in c, or may even be peculiar to one or the other, although there is no doubt that the great 
majority of the specimens are from these lower beds. 
MDCCCLX. 2 Q 
