From the published figures, they seem to correspond to the earlier Acheulean or to the Chellean type.
Since Chellean times all three rivers have silted up their channels.
This region was undoubtedly favorable to the flint workers of Pre-Chellean and Chellean times.
Below, to the right, is a very primitive instrument of Chellean type, being merely a sharpened pebble.
The Chellean implements are found in the gravels of the diluvium on the pebbly surface.
These deposits are believed to correspond with the period of Chellean and early Acheulean industry.
Chellean probably represents the earliest work in Europe of a pre-Neanderthal type like Piltdown man.
The Chellean and the following Acheulean industry was carried on here on a very extensive scale.
The type station of the Chellean culture is somewhat east of the present town of Chelles.
The Chellean implements, which precede those of Mousterian type, are commonly associated with a fauna of southern affinities.