Men of the Old Stone Age: Their Environment, Life and Art

by Henry Fairfield Osborn

Fig. 26. The musk-ox, belonging to the tundra region of the arctic circle, which is reported to have migrated as far south as the southern coast of England during the First (Günz) Glacial Stage.

The First Interglacial Stage. Eoliths

Proofs that a prolonged cool wave passed over Britain during the first glaciation are seen in its after effects, namely, in the modernization of the forests and in the disappearance both in Britain and France of a very considerable number of animals which were abundant in Upper Pliocene times. Yet by far the greater part of the Pliocene mammal life survived, a fact which tends to show that, while very cold conditions of climate and great precipitation of moisture may have characterized the regions immediately surrounding the ice-fields, the remainder of western Europe at most passed through a prolonged cool period during the climax of the First Glacial Stage. This was followed during the First Interglacial by the return of a period somewhat warmer than the present.

This First Interglacial Stage is known as the Norfolkian, from the fact that it was first recognized in Europe in the deposits known as the 'Forest Bed of Cromer,' Norfolk, which contain rich records not only of the forests of the period, but of the noble forms of mammals which roamed over Great Britain and France in Norfolkian times. The forests of Norfolk, in latitude 52° 40' N. mainly abounded in trees still indigenous to this region, such as the maple, elm, birch, willow, alder, oak, beech, pine, and spruce, a forest flora closely corresponding to that of the Norfolk and Suffolk coasts of England at the present time, although we find in this fossil flora several exotic species which give it a slightly different character.[(9)] From this tree flora Reid concludes that the climate of southeastern England was nearly the same as at present but slightly warmer.

We note especially that a very great change had taken place in the entire disappearance in these forests of the trees which in Pliocene times were common to Europe and America, as described above; in other words, the flora of Europe was greatly impoverished during the first cold wave.

In southern France, as at the present time, the interglacial climatic conditions were milder, for we find numerous species of plants, which are now represented in the Caucasus, Persia, southern Italy, Portugal, and Japan. Thus the First Interglacial Stage, which was a relatively short one, enjoyed a temperature now belonging about 4° of latitude farther south.

This First Interglacial Stage is also known as the St.-Prestien, because among the many localities in France and Italy which preserve the plant and mammal life of the times that of St. Prest, in the Paris basin, is the most famous. Here in 1863 Desnoyers[(10)] first reported the discovery of a number of mammal bones with incision lines upon them, which he considered to be the work of man. These deposits were regarded at the time as of Pliocene age, and this gave rise immediately to a wide-spread theory of the appearance of man as early as the Pliocene. The human origin of the incisions discovered by Desnoyers has long been a matter of dispute and is now regarded as very improbable. Similar lines may be of animal origin, namely, marks left by claws or teeth, or due to accidental pressure of sharp cutting surfaces. However, we do not pretend to express an opinion of any value as to the cause of these incisions. Supposed confirmation of the evidence of Desnoyers of the existence of Pliocene man was the alleged finding by Abbott of several worked flints, two in situ, in the 'Forest Bed of Cromer,' Norfolk. Many years later in similar deposits at St. Prest were discovered the supposed 'eoliths' which have been referred to the Étage Prestien by Rutot. The age of the St. Prest deposits is, therefore, a matter of the very highest interest and importance.

Fig. 27. The giant deer (Megaceros), which first appears in western Europe during the First Interglacial Stage, probably as a migrant from the forested regions of Eurasia. After a painting by Charles R. Knight, in the American Museum of Natural History.

St. Prest is not Pliocene; it is rather the most ancient Pleistocene deposit in the basin of Paris,[(11)] and these incised mammal bones probably date from the First Interglacial Stage. The bed which has yielded the incised bones and the rich series of fossils consists of coarse river sands and gravels, forming part of a 'high terrace,' 98½ feet (30 m.) above the present level of the river Eure. This, like other 'high terraces,' contains a characteristic First Interglacial fauna, including the southern mammoth (E. meridionalis), and Steno's horse (E. stenonis). We also find here other very characteristic early Pleistocene mammals, such as the Etruscan rhinoceros (D. etruscus), the giant hippopotamus of early Pleistocene times (H. major), the giant beaver of the early Pleistocene (Trogontherium), three forms of the common beaver (Castor), and one of the bison (Bison antiquus). This mammalian life of St. Prest is very similar to that of Norfolk, England; to that of Malbattu in central France, Puy-de-Dôme; of Peyrolles, near the mouth of the Rhône, in southern France; of Solilhac near Puy; of Durfort, Gard; of Cajarc, Lot-et-Garonne; and finally to that of the valley of the Arno, in northern Italy.