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the Quadrumana were formerly distributed over parts of the earth's surface, which at the present day, are so far altered as regards the climate and vegetable productions, as to be unfit for their existence.
ART. V.- Illustrated Zoological Notices. By EDWARD CHARLES
WORTH, F.G.S. &c.
(Continued from page 353.) 1. On the discovery of a Portion of an Opossum's Jaw in the London Clay,
near Woodbridge, Suffolk. 2. On some Fossil Teeth of the Genus Lamna, from the same deposit. A visit to the county of Suffolk, made within the last few days, has put me in possession of some fossil remains from the spot in which the fragment of an extinct macacque has been procured by Mr. Wood; and as the subject is one of the highest interest, I am anxious that the additional information which I have obtained should accompany the important communication made by that gentleman to the present number of the Magazine of Natural History.
I believe it was in the early part of 1837, that Mr. William Colchester, of Ipswich, who had then recently directed his attention to the fossils of the crag, showed me the molar tooth of some small mammiferous animal, which had been taken from a clay-pit near Woodbridge, quarried for the purpose of making bricks. From the character of the tooth I saw at once that it could not be referred to any of our indigenous quadrupeds, though I was unable from recollection to determine the genus, or even family, to which it probably belonged.--As the tooth was associated with those of sharks, and the quarry in the London clay district, Mr. Colchester supposed it to be a London clay fossil; and upon going over with him to visit the spot, I saw no reason for suspecting the deposit to be of more recent date, except the then unprecedented fact of mammiferous remains occurring so low down in the tertiary series. Aware of the important nature of the fact, assuming our estimate of the age of the bed to be correct, Mr. Colchester offered to place the fossil at my disposal, in the event of
my being inclined to record the circumstances of its discovery in the Magazine of Natural History. I should certainly have done so at the time, had I not felt that before announcing so novel a fact in the history of English tertiary Geology, there were reasons which called for a most careful examination of such sources of fallacy as might be present. The visit which I paid to the quarry was a very hurried
and as the crag was not here resting upon the surface of the clay, the evidence which would have been decisive—that of immediate superposition, was absent. The clay itself was destitute of fossils, and its thickness was not greater than that which
be sometimes seen in far more recent argillaceous deposits in Suffolk and Essex, and which deposits might readily be confounded with the London clay, in the absence of organic remains. In addition to this, I remarked that the sharks' teeth, at that time the only fossil remains found with the mammiferous tooth, were quite as characteristic of the crag as of the London clay, being all of small size, and of the forms which are common to both deposits.These reasons made me determine to postpone a notice of this interesting specimen, until I should have satisfied myself, as far as possible, as to the antiquity of the stratum in which it was imbedded. Nearly three years, however, have now elapsed since its discovery was communicated to me, and during the hasty visits that I have subsequently paid to that part of the country, having never put my original intention into execution, or applied to Mr. Colchester for the specimen, it was handed over to Mr. Lyell on one of his late excursions to Suffolk, and I believe will be noticed by him at the Birmingham meeting of the British Association.
In the early part of the present month I received from Mr. Wood the fossil remain which forms the subject of the joint communication from himself and Professor Owen; and as the discovery of an extinct quadrumanous animal greatly added to the importance of no error being committed with regard to the supposed age of the bed, for the purpose of setting at rest any doubt that might still have lingered in my own mind, I devoted a morning a few days since to the examination of the spot. After thoroughly exploring the geological features presented by the beds in the immediate neighbourhood of the place, I think the quarry may, without any hesitation, be assigned to the age of the London clay. Several quarries of crag occur within half a mile distance; and on crossing the river you have, a little nearer the town, a section of the clay and superimposed crag, similar to that exhibited by the coast line at Walton and Felixstow.
The annexed sketch, fig. 59, without its being drawn to any very accurate scale, will convey an idea of the probable section which the beds of clay and crag would exhibit on either side the Deben, the presumed length of the section being three miles.
I was much disappointed in this last visit to the quarry to find that the stratum of sand in which the fossils are found was not exposed, owing to its lying below the clay, and the small quantity required in manufacturing the bricks. Some of the sand however had been laid aside, and was being sifted by a daughter of one of the workmen, who picked out the sharks' teeth, which, with about three or four per cent. of fine shingle, formed the residuum. The teeth were plentiful enough, but I could not detect the slightest fragment of a shell. The foreman told me that they had sunk about ten feet into the sand, without passing through it. It would be desirable to ascertain at what depth the chalk is there met with, but this point I had not the means of determining : probably it is not far below the surface, and this sand may perhaps separate the chalk from the overlying clay.
Upon my calling on Mr. Colchester, I found that he had been so fortunate as to have added to his previous discoveries that of the interesting fragment represented at fig. 60, con
(a) Portion of the lower jaw of the fossil Opossum, enlarged one half.
(6) View of the crown of the tooth, twice the natural size; (seen from within). sisting of a portion of the right ramus of the lower jaw of an opossum, in which one of the false molars is happily retained. The tooth in its symmetrical form, united with the indication of an anterior as well as posterior heel or talon, does not agree with any species of didelph with which I have as yet been able to compare it, but I think no doubt can be entertained of the generic or family affinities indicated by the characters which it exhibits. Judging from the empty alveoli on either side, the tooth appears to be the one immediately succeeding the true molars : its posterior tubercle is strongly developed, and divided longitudinally by a prominent ridge, the continuation of which forms the posterior edge of the body of the tooth. At the base of the anterior root of the tooth the opening of a foramen is seen, on the outer surface of the bone.
It is unnecessary to offer any comments on the interest of the additions now made to the extinct Fauna of this island, by the discovery of Quadrumana and marsupials in the London clay.
These additions probably constitute only the commencement of a series of discoveries, which will be brought to light in the same quarter; as Mr. Colchester, who holds the quarry, has made arrangements for the careful examination of all the sand which shall be subsequently removed. The connection of this enquiry with the subject of M. d'Orbigny's papers in the Journal of the French Academy, and the Bulletin of the Geological Society, should not be overlooked. It seems as though the phenomena in the present case would admit an inference very similar to that which he drew from an examination of the beds above the chalk in the neighbourhood of Meudon, and respecting which he remarks, --“Qu'il existe, à la partie inférieure de l'argile plastique, des caractères nouveaux démontrant surtout que
divers genres de mammifères vivaient à l'époque où cet étage s'est formé.”
(a & d) Teeth of Lamna agreeing in form with species abundant in the London clay & red crag. (b) Tooth probably of the same genus, but of an undescribed species, provided with quadrate
Tooth of Lamna with two pairs of denticles. (e) A tooth, of which the form probably depends upon its situation having been near the ter
mination of the series.
I selected a few of the sharks' teeth found in this deposit, from several hundred in the possession of Mr. Colchester, for the purpose of illustration. I believe all yet discovered may be referred to the genus Lamna, and to species which occur in both the crag and London clay, so that at present the identification of the bed from the evidence furnished by organic remains, must be looked upon as a desideratum. The teeth of the genus Otodus, though not uncommon in the London
clay of Suffolk, have not been noticed in the present deposit, whilst, on the other hand, there are no traces of the genus Carcharias to favor the opinion of its age agreeing with that of the crag. The average size of one hundred teeth, if compared with the same number from the Harwich cliffs, will be found about one third smaller. Their colour and general aspect corresponds most closely with the appearance presented by the small sharks' teeth from Malta, and some of the continental tertiary deposits, and presents a singular contrast to those found in the red crag, or the ordinary beds of the London clay formation. As Mr. Wood has remarked, they do not appear to have been subjected to the slightest bouldering, a circumstance satisfactorily established by the perfect condition of the lateral denticles.
Art. VI.-A Systematic Catalogue of the Fossil Plants of Britain.
By John Morris Esq. The study of fossil Botany, equally interesting and important as any other branch of Natural History, is rendered more difficult in consequence of those parts which, in a recent state, afford the most ready means of generic distinction, being rarely preserved: however, Botanists, well acquainted with the structure of existing vegetation, have, by an attentive examination of the best-preserved portions, been enabled to decipher many of the characters of the ancient Flora. In the
present catalogue I have included not only the fossilized remains peculiar to Britain, but many of the more interesting specimens which have hitherto been found only in continental deposits. The general arrangement of the greater portion of this catalogue, as well as the generic characters, have been adopted from the views entertained in the works of Messrs. Lindley and Hutton,' Witham, Brongniart, 2 Sternberg, 3 &c., and for the cryptogamic part, more especially the Filices, to
1 Lindl. and Hutt. "The Fossil Flora of Great Britain,' by Lindley and Hutton. London: 1831-1836.
2 Brong. Prod. "Prodrome d'une Histoire des Végétaux Fossiles,' par M. A. Brongniart. Paris : 1828.
Brong. Hist. Histoire des Végétaux Fossiles. Paris : 1828.
3 Sternb. Versuch einer geognostich-botanischen Darstellung der Flora der Vorwelt,' C. von Sternberg. Leipsic and Prague: parts i.-iv. tab. 1-58, 1820; parts v. and vi. tab. 1--26, 1833.