84 POPULAR SCIENCE MONTHLY. 



selenite, besides bones and teeth of the Eocene deer-like Anoplotherium, 

 and of Dinotherium, an early forerunner of the elephant. 



Upon this lower Tertiary marine bed rest the fresh water Quaternary 

 beds, the series beginning with the lowest Pleistocene beds, passing 

 through beds of supposed glacial origin containing transported 

 pebbles, up into postglacial strata containing Neolithic implements. 



The transition from the Tertiary formation is sudden. When the 

 lowest Quaternary beds were deposited, the Eocene marl beds had been 

 elevated, become dry land and exposed to the erosive action of the winds 

 and rains. A long interval passed between the time of deposition of 

 the Tertiary beds and the Pleistocene deposits which now cap them. It 

 is to be observed that the later Tertiary formations (Oligocene, Miocene 

 and Pliocene) are absent. 



The Quaternary deposits at Chelles are divided into four distinct 

 fresh water beds, each differing in age and in their materials, and as 

 exposed by the workmen the whole series appears to be about 25 to 30 

 feet in thickness. They are as follows: 



D, E. The lowest bed, that directly overlying the Eocene marl, con- 

 sists of rolled pebbles and grayish sand, the mass being often cementedby 

 calcareous infiltrations. This bed contains the Chellean implements. 

 (What is apparently an upper division of this bed (D) is what the Abbe 

 Bonno calls the Acheulean, and from it have been taken axes like those 

 found at St. Acheul near Amiens.) In this lowest bed also occur the 

 remains of Elephas antiquus, Rhinoceros merckii, etc. 



C. A deposit, not forming a continuous bed, and only seen in places, 

 of water worn coarse gravel and small pebbles derived from Tertiary 

 gravels, and called by Bonno 'sables moyensf This is the red drift, 

 'diluvium rouge,' of Ameghino. It abounds in rolled, broken, some- 

 times entire, Tertiary marine shells which have been brought by fresh- 

 water streams probably from Lizy-sur-Ourcq and from Etrepilly a few 

 miles to the northeastward, or perhaps from Soissons to the north 

 (Bonno). 



B. A second layer of drift or rolled and transported gravel, con- 

 taining flint implements of the Moustierian epoch, and bones of the 

 mammoth. 



A. A thin bed of gray clay of the age of the Swiss Lake-dwellers, 

 in which occur polished stone axes. 



The chief center of interest is of course the lowest bed (D, E), that 

 containing the worked flints. These are the celebrated Chellean axes, 

 which are of various sizes, no two exactly alike, which were worked out 

 by chipping from flint nodules, the flint being derived from the chalk 

 deposits. These crude weapons were probably used in the chase or in 

 battle, and were not mounted, but held in the hand. Almond-shaped, 

 in the form of a 'coup de poing,' they were worked on both sides or 



