SOCIETY OF THE UNIVERSITY OK ABERDEEN. 43 



cause, whereas those of the mounds are of full size and the oyster 

 is found plentifully in them. Hence we may infer that in the days 

 of these aboriginal hunters and fishers the ocean had much freer 

 access to the Baltic than at present or even within historic times, 

 probably by way of Holland and Northern Germany. At first sight 

 it might be thought that the Baltic Sea would be more salt than 

 the open ocean, due to concentration, but when we consider that it 

 is practically a lake with several large rivers draining the north- 

 western part of Europe running into it, it is obvious how the amount 

 of salts has diminished in the course of ages. Such a geological change 

 must have taken a very long period for its accomplishment ; it shunts 

 back the time when these mounds must have been formed very con- 

 siderably and furnishes the strongest proof of their great antiquity. 



That this ancient race ventured out to sea in canoes such as are 

 found in the peat mosses, hollowed out of the trunk of a single tree, 

 is testified by the bones of herring, cod, fiounder and other ocean 

 animals found in the "kitchen-refuse heaps". 



They do not seem to have been cannibals, for no human bones 

 are mingled with the spoils of the chase. Skulls, however, have 

 been found not only in peat but in accumulations of the Stone period. 

 These skulls are small in capacity, round, and have very prominent 

 superciliary ridges. This race was probably small of stature, as is 

 evidenced by limb bones, round-headed with overhanging eyebrows, 

 not unlike the modern Laplander. 



The human skulls of the Bronze age are of a more elongated form 

 and larger in size than the foregoing, pointing to the arrival of a new 

 race probably from the South and a driving out of the older in- 

 habitants. Only a few of these have been found, owing, no doubt, 

 to the custom prevalent among them of burning their dead and col- 

 lecting the remains in funeral urns. 



No traces of grain of any sort have hitherto been discovered, or 

 any other indication that the ancient people of the Stone age had any 

 knowledge of agriculture. 



Having collected so much data from Denmark and its pictur- 



