1890.] Archeology and Ethnology. 287 
alluvial soil which would be deposited each year in the lake Ton-le-Sap, 
likewise the numerous changes made in the shores of the lake during 
the ages this operation has been going on. 
On the retreat of the waters, the shores of the lake and little islands 
in it become dry. The people from the neighboring highlands come 
down, occupy these spots, and there appear flourishing villages, which 
are to last, however, only six months of the year, when they will be 
submerged by the next year’s inundation, the inhabitants being driven | 
to the highlands for safety. 
The geographic and hydrographic details being understood, we may 
now explain the prehistoric stations of the neighborhood. Not far 
distant from the border of this great lake there have been found 
numerous and vast Kjoekenmoeddings, or shell-heaps, many of which 
have been excavated by the natives to obtain the material for fabrica- 
tion of lime. It was from these shell-heaps that Mr. Jammes obtained 
the stone implements which have lately come into the possession of the 
National Museum. He discovered eighteen of these shell-heap 
stations, and excavated some of them. They are covered by a stratum 
of alluvial soil, the deposit of the floods. The depths or thicknesses 
of the shell-heaps were from thirteen to twenty-nine feet. They were 
composed of three layers quite distinct from each other, and each 
bearing evidence of a different civilization and an occupation by a 
different set of men. They were as follows, commencing at the top: 
The first stratum had the least thickness. In it were instruments of 
copper, though possibly some of bronze—hatchets, pins, bracelets, etc. 
There were pieces of stone finely worked. The pottery was of the 
most perfect form, and some of it was ornamented with the ordinary 
designs of the bronze age. 
In the second stratum were objects in stone mixed with those of the 
bronze or copper, and this is considered to mark an epoch of transition 
between the bronze age and the stone age which formed the lower 
stratum. 
This lower stratum was the deepest of the three, and here were found 
the implements and pottery which belonged to the age of polished stone. 
These shell-heaps have required a long period of time. Some of 
them were distant more than fifty miles from the great lake, and it is 
supposed that at their epoch they were on the borders of the lake thus 
extended. In the lake of Ton-le-Sap are now found several species of 
the same shells and mollusks as those of the prehistoric stations, but 
the latter are thicker and heavier. It is certain from this and other 
discoveries that the period of the polished stone age is very ancient 
