A Day's Elephant Hunting in Essex. 45
from milder temperature back to Lapland rigours, might
occur. The higher vegetable forms might be arrested,
checked, and in places destroyed, and the adventurous
vanguard of the incoming animals starved or driven back,
but the land was now open to the great Europasian invasion.
The pine, the fir, and the birch, and turf-forming grasses,
self-sown and self-advancing, could now invade the land,
ousting the weaker herbaceous forms and preparing the
country for the "age of elephants" which was soon to set in.
In the rigours of winter the musk-ox foraged the land, and
the Arctic rodents—the lemmings, the voles, and the hares
—were preyed upon by the fox and the glutton, and when
berries and roots had failed by the brown bear. The
summers began to lengthen, and the spreading pines and
firs were at length discovered by the first company of
migrant mammoths. The hardy but less gregarious woolly
rhinoceros, with its curious nasal horns, was seen in the
land. The wide-spreading moraine of south-eastern and
central England still stretched to the glacier foot on the
mountain districts of the Pennine, but in Essex and Middle-
sex it was now overgrown with forest and prairie, and
watered in summer with streams. Across the marshes and
through the forests of the former German Ocean, and
southward from the future Gaul, the invasion of the great
herbivores began. The animals of a more temperate zone
succeeded in south-eastern England as the musk sheep
retreated northwards. Herds of gigantic bison, uri, and deer,
and hosts of rodents came to the newly found feeding-ground.
Yet in spite of wolves and lions, the great vegetable feeding
mammalia lived and multiplied in the new and congenial
home. The mammoth became one of the commonest
animals of the Thames Valley; the shed milk teeth of
the calf, and the last overworn molar of the patriarch of
the herd, are amongst the most abundant fossil remains
at Ilford, Grays, Erith, and Crayford. It was the age
of the great herbivores, for it was also the age of the
yet unrestrained carnivores.* At least two species of wild
* See an interesting lecture by Professor Rolleston on "The Changes
introduced by Man in the Indigenous Flora and Fauna of Great