from the resorted layers at the base of the Fen Beds.

There is no definite chronological succession which will hold throughout the Fens. The variations observed are geographical—clay, marl, peat, etc., alternating in different order in different localities and subaerial, fluviatile, estuarine, and marine, having only a changing topographical significance.

The Fen Beds crept over an area where the underlying formation had been undergoing vicissitudes due to slow geographical changes—changes which, being at sea level and near the conflict of tides and upland water, produced irregular but often important results.

There is not in the Fens any continuous record of what took place between the age in which the Little Downham Rhinoceros was buried in the gravel and that in which the Neolithic hunters poleaxed the Urus in the peat near Burwell.

  Palaeontology of Fens.

Nor do we find any constant succession in the fauna and flora in the sections in the Fens any more than we find a uniform distribution of plants and animals over the surface to-day. The most numerous and largest specimens of the Urus I have obtained from near Isleham: the best preserved Beaver bones from Burwell. Modern changes of conditions have limited the district in which the fen fern (Thelypteris) or the swallow-tailed butterfly may now be seen; but nature in old times produced as great changes in local conditions as those now due to human agency.

When we compare the fauna of the Areniferous Series with that of the Turbiferous, although there is not an entire sweeping away of the older vertebrate and invertebrate forms of life and an introduction of newer, there is a marked change in the whole facies.

There is plenty of evidence about Cambridge of the gradual extermination of species still going on. Indeed, I feel inclined to say that there is no such thing as a Holocene age. I remember land shells being common of which it is difficult now to find live specimens, and my wife[6] has shown how the mollusca are being differentiated in isolated ponds left here and there along the ancient river courses above the town.

But we have not in older beds of the Turbiferous or newer beds of the Areniferous Series any suggestion of continuity between the two. There must have been between them an unrepresented period of considerable duration in which very important changes were brought about. Perhaps it was then that England became an island and unsuitable for most of the life of the Areniferous age.

Not only have we in the Turbiferous as compared with the Areniferous Series a change of facies but we have many "representative forms," a point to which that keen naturalist, Edward Forbes, always attached great importance.

We have for instance in the Fen Beds the Brown Bear (Ursus arctos) with his flat pig-like skull, instead of the Grizzly (Ursus ferox) of the Gravels with his broad skull and front bombé.

If we turn to the horned cattle we shall find a confirmation of the view that there was not an entire break between the Turbiferous and Areniferous fauna for the Urus (Bos primigenius) occurs in both. This species became extinct in Britain in the Turbiferous period and before the coming of the Romans, for no trace of it seems to have been found with Roman remains in this country; and indeed when we remember the numerous tribes, the dense population and high civilisation of the natives of Britain in Roman times it seems improbable that they can have tolerated such a formidable beast as this wild bull around their cultivated land.

Some confusion has arisen as to the description and the names of the Urus and the Bison. Caesar, who was not a big game hunter and probably never saw either, has given under the name Urus a description which evidently mixes up the characters of both. Both existed on the continent down to quite recent times and the Bison is still found in Poland, but later writers also have evidently confounded them. For instance, the Augsburg picture of the Urus is correct, but Herberstein's, which also is said to represent the Urus, is obviously that of a Bison. I have gone into this question more fully elsewhere[7].

The Urus (Bos primigenius) is common in the Fen Beds and is of special importance for our present enquiry, as there is in the Sedgwick Museum a skull of this species found in Burwell Fen with a Neolithic flint implement sticking in it. The implement is thin, nearly parallel sided, rough dressed, except on the front edge which is ground, and it is made of the black south-country flint. It is very different in every respect from the thick bulging implements with curved outlines, which being made of the mottled grey north-country flint or of felstone or greenstone suggest importation from a different and probably more northerly source.

This gives us a useful synchronism of peat, a Neolithic implement of a special well-marked type, and the Urus.

The Bison is the characteristic ox of the Gravels and never occurs in the Fen Beds; while the Urus, as I have pointed out above, occurs in both the Turbiferous and Areniferous deposits.

Bos longifrons is the characteristic ox of the Fen Beds and never occurs in the Gravels. It is the breed which the Romans found here, and we dig up its bones almost wherever we find Roman remains. I cannot adduce any satisfactory evidence that it was wild, that is to say more wild than the Welsh cattle or ponies or sheep which roam freely over wide tracts of almost uninhabited country. This species, like the Urus, has horns pointing forward, but the cattle introduced by the Romans had upturned lyre-shaped horns, as in the modern Italian, the Chillingham or our typical uncrossed Ayrshire breed, and soon we notice the effect of crossing the small native cattle (Bos longifrons) with the larger Roman breed.

The Horse appears to have lived continuously throughout Pleistocene times down to the present day and to have been always used for food. Unfortunately the skull of a horse is thin and fragile and therefore it has been difficult to obtain a series sufficiently complete to found any considerable generalisations upon it. The animal found in the peat and alluvium appears to have been a small sized, long faced pony.

The appearances and reappearances of the different kinds of deer is a very interesting question, but it will be more easily treated when I come to speak of the Gravels of East Anglia. I will only point out now that neither of the deer with palmated antlers properly belongs to the Turbiferous series. The great Irish Elk (Cervus megacerus) has not been found in the Fen Beds. Indeed it is not clear that in Ireland it occurs in the peat. The most careful and trustworthy descriptions seem to show that its bones lie either in or on top of the clays on which the peat grew.

The other and smaller deer with palmated antlers, namely, the Fallow deer (Cervus dama), were reintroduced, probably by the Romans, and although some of them have got buried in the alluvium or newer peat in the course of the 1500 years or so that they have been hunted in royal warrens in East Anglia, they cannot be regarded as indigenous or indicative of climate or other local conditions.

Remains of the Red deer (Cervus elaphus) and of the Roe deer (Cervus capreolus) are common in the Fen Beds; both occur in the Gravels also; and both are still wild in the British Isles. Unlike the Red deer, which lives on the open moorland, the Roe deer lives in woods and forests. And this is an interesting fact in its bearing upon our inferences as