Table of Measurements of Limb-bones of Wolf.

§ 7. Remains mark Route of Migration.-The number of individuals represented by the remains is, so far as I can estimate it, as follows:

Bison
Reindeer..
Grisly Bear.
Wolf

40-60,

20-30,

4- 5,

7.

The herbivores are largely in excess of the carnivores; and the Bisons were far more abundant than the Reindeer during the time of the accumulation of the remains.

From the position of Windy Knoll at the head of the grand defile of the Winnetts, which would offer free passage to the mammalia in their migrations from the valley of the Derwent into the plains of Lancashire and Cheshire, it is very probable that these remains mark one of the routes by which the Bisons and Reindeer passed from the east to the west of England. They may have been accumulated at a drinking-place, as is suggested by Mr. Pennington.

The association of the carnivores with the herbivores may be satisfactorily explained on the hypothesis that they followed the Bisons and Reindeer in their migrations. With regard to the latter animals, Admiral von Wrangell gives a most graphic account of what he observed in his journey through the stony Tundra near the river Baranicha, in North-eastern Siberia *.

"I had hardly finished the observation," he writes, "when my whole attention was called to a highly interesting and, to me, a

* Narrative of an Expedition to the Polar Sea in 1820-23,' edited by General Sabine [London, 1840], p. 294.

perfectly novel spectacle. Two large migrating bodies of Reindeer passed us at no great distance. They were descending the hills from the N.W., and crossing the plain on their way to the forests, where they spend the winter. Both bodies of deer extended further than the eye could reach, and formed a compact mass narrowing towards the front. They moved slowly and majestically along, their broad antlers resembling a moving wood of leafless trees. Each body was led by a deer of unusual size, which my guides assured me was always a female. One of the herds was stealthily followed by a wolf, who was apparently watching for an opportunity of seizing any one of the younger and weaker deer which might fall behind the rest; but on seeing us, he made off in another direction. The other column was followed at some distance by a large black bear, who, however, appeared only intent on digging out a mouse's nest every now and then-so much so that he took no notice of us."

The Bisons also, on the plains of Colorado, are accompanied in their migration by wolves and bears, which prey upon the stragglers.

Such a migration as this would satisfactorily account for the presence of vast quantities of the bones of Bisons and Reindeer in so limited an area as twenty-two cubic feet.

§ 8. Migration of Bison at different season from that of Reindeer.A careful examination of the young teeth of the Bisons and Reindeer has further led me to conclude that these two animals migrated through the pass of the Winnetts and over Windy Knoll at different times of the year. The unworn milk-molars and the germ of milkteeth of the former animal prove that calves not more than three or four months old formed part of the herds, which consequently must have been in that district within three or four months of calving-time, or May-in other words, in the summer and autumn. On the other hand, the milk-molars of the Reindeer were very scarce; and of them only one (the last in the series) possessed imperfect fangs. It seems, therefore, tolerably certain that they were not in the district in the summer or autumn, their calving-time (according to Sir John Richardson) being May*. We may therefore picture to ourselves the herds of Bison traversing the district in the summer and autumn, and the herds of Reindeer in the winter and early spring, attended by the beasts of prey (bears and wolves), as is now the case in Siberia and in Colorado.

A parallel case to this of Windy Knoll is afforded by the accumulation of bones of Reindeer, Bison, Hare, Bear, and Wolf which was discovered by Captain Luard, R.E., in 1866, in digging the foundation of a cavalry-barracks at Windsor. I found that the first two of these animals were by far the most abundant. The remains in question had most probably been derived from a ford higher up the then stream of the Thames, which offered passage to migratory bodies for many years +.

§ 9. The Deposit of Pleistocene Age.-It will have been remarked that no extinct animals have been found in this deposit. Is it, then,

* Fauna Boreali-Americana,' vol. i. p. 242.

+ Sec Popular Science Review,' January 1868, p. 37.

to be referred to the Pleistocene age? According to Prof. Lartet it would belong to the latest stages, or those of the Bison and Reindeer. That it belongs to the Pleistocene is to me tolerably certain, because of the presence of large numbers of Reindeer and Bison, which in the succeeding period were very rare in this country. But whether it belongs to an age when the Mammoth and Woolly Rhinoceros had become extinct, seems to be an open question, since both those animals have been found in the district, and since it is extremely improbable that all the animals would migrate by the same routes. Nor is there any proof from the physical character of the superficial strata as to its relation to the Glacial period. It stands on the edge of the non-glaciated area of the eastern side of the Pennine chain of hills, where the boulder-drifts so largely developed in the west cease to be found. It is therefore also an open

question as to whether it is of Pre- or of Postglacial age.

DISCUSSION.

Mr. EVANS, referring to the bronze celt mentioned by Mr. Pennington, stated that he had never seen one of a similar character, and that he thought it to be of modern workmanship. It was found, on analysis, to contain nearly 12 per cent. of zinc, which proved, at any rate, that it did not belong to the Bronze age. He said that the bones discovered were of great interest, as corresponding with those of Pleistocene age in other districts. The great quantity of Reindeer-remains was remarkable, as such numbers had not previously occurred in that part of England.

Mr. CHARLESWORTH remarked that the difficulty connected with the finding of great numbers of mammalian remains was not confined to the case of caves. He instanced the case of Happisbro', on the Norfolk coast, where an oyster-bed was discovered in 1812 or 1813, and the fishermen brought up in their dredges immense numbers of mammalian remains. About 2000 teeth of Mammoths or Elephants, representing some 300 or 400 animals, were thus obtained in about fourteen years.

Mr. EVANS observed that the accumulation in Windy-Knoll fissure might be simply due to accidents occurring to herds of Bisons and Reindeer passing that way. If the fissure remained open for about 1000 years, and 2 Bisons fell into it every 50 years from herds of 100 or more passing, the number found would easily be produced, and the survivors would probably hardly miss their lost companions.

18. On the RELATIONS of the CAMBRIDGE GAULT and GREENSAND. By A. J. JUKES-BROWNE, Esq., B.A., F.G.S., of the Geological Survey of England. (Read January 13, 1875.)

Part I.-Stratigraphical Relations.

1. The Gault and Chalk-marl in Cambridgeshire.

2. The Gault and Chalk-marl in Bedfordshire.

3. The Gault and Upper Greensand in Buckinghamshire.
4. The Upper Gault in Bucks and Bedfordshire.

5. The Gault and Greensand of the Weald.
6. Conclusions from Stratigraphical Evidence.

Part II.-Paleontological Relations.

1. Natural Division of the Cambridge Fauna.

2. Further Analysis of the Fauna.

3. Conclusions from Palæontological Evidence.

4. Remarks on the Synonymy of certain Species.

5. List of the Cambridge Fossils, and Tables of Range.

INTRODUCTION.-I cannot do better than preface the following observations with a few words from the pen of Mr. Davidson in the Geological Magazine' for 1869 *. These are:

"Some considerable difference of opinion has been expressed, not only at home, but also on the Continent, as to the real value or position of the well-known Cambridge Greensand or Phosphate-bed. Some consider it to constitute a portion of the Upper Greensand, while others would refer it to the upper portion of the Gault; and, abroad, some geologists constitute a distinct stage, for which the term Vraconnien is proposed..... It is a point of great importance to determine the exact age of this Cambridge bed; and in making a palæontological comparison there are several points in the case which will call for especial caution; and, as suggested by Mr. Judd, we must in the first place determine whether there are any derived fossils in the bed (so often met with in beds of phosphate nodules)." In accordance with the above remarks the present communication has for its main objects:—

1. To determine the true position of the Cambridge bed in the Cretaceous series.

2. To trace the extent of country along which the formation may be followed.

3. To investigate the origin and age of its organic contents.

Before, however, the above-quoted paragraphs had come under my notice, the Cambridge nodule-bed had been for. three or four years my especial study, which a residence in Cambridge gave me * 'Continental Geology," Geol. Mag. vol. vi. p. 259.

great opportunities of prosecuting. I wish therefore in the first place to say a few words regarding the circumstances under which this paper came to be written.

It was in 1872 that the idea first occurred to me that the so-called Cambridge "coprolites" had not originated where they are now found, but had been derived from some part of the underlying Gault. This supposition was confirmed by subsequent conversation on the subject with the Rev. T. G. Bonney, who had, I found, for some years held the same opinion regarding their origin. His views were published in a paper read before the Geologists' Association in February, 1872, in which he gives a general review of the contents of the bed, notices the large proportion of Gault forms, and draws attention to the waterworn character of these fossils and to the eroded surface of the Gault below. This excellent paper, by its general survey of the questions connected with the Cambridge bed, was admirably fitted to clear the way for further investigations. It only remained therefore to extend the area of observation beyond the immediate neighbourhood of Cambridge, and to institute a thorough palæontological comparison between the Cambridge fauna and those of other beds between the same horizons.

With the view of assisting Mr. Bonney I at once commenced this latter undertaking in the Woodwardian Museum; the work, however, did not progress rapidly, till the presence of Mr. F. G. H. Price in Cambridge enabled me to obtain from him more accurate information regarding the Gault fauna, which he has so systematically worked out at Folkestone*. This locality I had also the advantage of visiting with Mr. Price, and of collecting from the Upper Gault nodules and fossils identical with those on our Cambridge "coprolite" heaps. My next step was to try and find the representative of this Upper Gault, with its sandy bed, in the more northern area; and, acting on information kindly given me by Mr. Whitaker, I proceeded to Cheddington, in Bucks, and thence through Bedfordshire to Hitchin.

In this traverse I was fortunate in finding the beds of which I was in search, and also succeeded in fixing the extreme south-west limit of the Cambridge nodule-bed.

Having thus acquired sufficient material for publication, I communicated the results to Mr. Bonney, who had already given the subject so much consideration, and with whom it would have afforded me much pleasure to be associated. He, however, generously waived his participation in the proposed paper, and persuaded me to publish the results of my own investigations.

In doing this I propose first to examine the physical relations of the Gault, Greensand, and Chalk in the counties of Cambridge, Bedford, and Bucks, and to compare them with the same formations in the south of England; secondly, to examine the paleontological relations between the Cambridge fauna and that of other beds between the Lower Gault and Chalk-marl (Albien and Rhotomagien), both in England and on the Continent.

*See Quart. Journ. Geol. Soc. vol. xxx. p. 342.