310 LECTURE XI. 



pared with other regions of the earth. Whilst in the middle of 

 the tertiary period^ palms were growing in Switzerland^and high 

 Californian pine trees in Iceland^ the end of the tertiary period 

 was marked by a number of evergreen plants^ with a temperature 

 in Switzerland hke that of Italy ; on the shores of the Medi- 

 terranean neither plants nor animals show the evidence of any 

 conditions which might have been detrimental to the life of 

 man in the tertiary period. Just as at present^ man can live in 

 the same chmate as the ape, the hippopotamus, the elephant, 

 and the rhinoceros, so could he have existed side by side with 

 these animals and their corresponding Flora in the tertiary 

 period. That human fossils may, at some future time, be 

 found in the tertiary strata, is rendered probable by the dis- 

 coveries of M. Desnoyers, member of the French Academy, 

 who found traces of the existence of man in strata older than 

 the quaternary deposits. These consist in strife, or incisions, 

 some very fine, which were apperently produced by the aid of 

 flint knives, upon the bones of large animals, found in a sand- 

 bed of St. Prest, near Chartres, on the banks of the Eure. 



" The sand-beds of Saint-Prest," says Laugel, in his descrip- 

 tion of the departments of Eure et Loire, in 1860 — that is to 

 say, at a time when the dispute about the relative age of the 

 diluvial beds had not yet commenced, and consequently there 

 was no motive for ascribing to these strata a greater or less 

 antiquity — " the sand-beds of Saint-Prest have nothing what- 

 ever to do with the diluvial deposits proper, which, on their 

 part, are connected with the excavation of the valleys. They 

 fill up a lateral depression which must have existed before the 

 excavation of the Eure valley. The section of the sand-pit 

 presents, beneath a thick layer of surface clay first, banks of 

 gravel, then beds of white sand containing pebbles, and at the 

 bottom beds of very fine white sand. In the whole sand-pit, 

 excepting these lower fine sand-beds, there are found large 

 worn-down blocks of flint, sand-stone, sometimes a siHceous 

 conglomerate ; some veins in the lower parts contain also por- 

 tions of felspar, mixed with transparent quartz." 



The sand-pit of Saint-Prest contains, in the lowest part, 

 imbedded in the fine sand, a large number of the bones of 



