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eastwards through Shensi to Shansi; its extreme eastern limit being indicated by the elephant's tooth from Shanghai.
Hitherto we have had no evidence of the extension of this fauna to the northward of Kansu, although the circumstance that the Whang-ho flows into Mongolia south of the Ala-Shan mountains (through which there is a gap into the great Gobi desert), suggests that it must have reached these regions. Recently my friend Prof. Howes put into my hands a small collection of mammalian bones and teeth which had been sent to Prof. Huxley as coming from Mongolia.
Although some of the specimens are not unlike Siwalik fossils, others are quite different; and since the latter closely resemble the Szechuen cave-bones, I have no doubt that they are all of Chinese origin, and have no reason to suspect their reputed source. The list of specimens is as follows, viz.:
1. Part of the mandible of a hyæna.
With the exception of No. 14, all the specimens are thoroughly mineralized, the cancellæ and medullary cavities of the bones being filled either with crystalline spar, or with a hard reddish clay, or sandstone. From their pure white colour, it seems probable that Nos. 4, 5, 6, and 8 were obtained from a cavern-deposit; the matrix adhering to them being a reddish sandstone. No. 1 is of a pale-brown colour, but also has a somewhat similar matrix; the teeth being stained of a greenish colour, quite unlike the pure white of No. 8. Since the condition of this jaw is not unlike that of many Punjab Siwalik fossils, I think it was probably obtained from an ordinary sedimentary deposit. A similar origin may, perhaps, be assigned to some of the other specimens, such as Nos. 2, 9, 10, 11, and 12, which have a more clayey matrix; Nos. 10 and 11 being not unlike some of the fossils obtained from the typical eastern Siwaliks. With regard to the origin of the remaining specimens I am more doubtful.
The interest attaching to the specimens consists not only in that they carry (if their reputed place of origin be the true one) the Chinese Pliocene mammalian fauna to a more northern district than has been hitherto known, but that they indicate two Indian Siwalik species not previously recorded from Chinese territory. Moreover, one of them affords important information as to the structure of a Siwalik species.
Hyæna macrostoma, Lyd. The first specimen I have to notice is the fragment of a hyæna's jaw (No. 1) represented in woodcut, fig. 1.
This consists of the imperfect hinder portion of the left ramus of the mandible,
containing the broken carnassial p. 4. mi.
tooth (M. 1), and the roots of the fourth premolar. That it belongs to a hyæna is evident from the structure of the carnassial, which, while of the feline type, differs from that of all Felidæ in possessing a well
developed hind talon. This tooth Fig. 1. Outer view of the superior border of part of the left ramus of the mandible of Hyæna ma
has a length of o'0235 and a width crostoma from Mongolia, i.
of o‘on. The roots of the last pre
molar indicate that that tooth was of a very long and narrow form, quite different from that of existing hyænas. Moreover, the present specimen is characterized by the circumstance that the last premolar and the carnassial are placed in the same antero-posterior line, whereas in the more typical hyænas the long axis of the one is very oblique to that of the other.
In all these respects this specimen agrees with two very aberrant species of hyæna, respectively known as Hyæna chæretis, Gaudry, from the Pikermi beds of Attica, and H. macrostoma, Lydekker, from the Punjab Siwaliks; the former being the type of Hensel's genus Lycyæna. Compared, indeed, with the lower jaw of H. macrostoma (of which there is a cast in the British Museum) the present specimen can only be distinguished by the somewhat smaller depth of the ramus—a feature which may well be due to difference of age or sex. And it may be noted that while the present specimen (as deduced from the amount of wear the tooth has undergone) belongs to a comparatively young animal, the Siwalik jaw indicates a considerably older individual.
So far, then, as can be determined from the lower jaw, there are no reasons for separating the Mongolian hyæna from the Siwalik H. macrostoma. The interest of the present specimen does not, however, end here. Both in H. chæretis and H. macrostoma it has hitherto been unknown whether (as in H. græca and H, sivalensis) there was a second lower molar, or whether (as in all the existing species) this tooth was absent. The present specimen shows its absence. Further, in the Pikermi species the lower carnassial has a very large hind talon, and an inner cusp rising from the hinder lobe of the blade. The carnassial being broken off in the Siwalik jaw, it was impossible to determine its relation to the Pikermi species in these respects. In the present specimen, however, there is no cusp on the inner side of the carnassial, while the talon is smaller than in H. chæretis. If, therefore, the Mongolian jaw be rightly referred to H.macrostoma, it enhances the distinctness of that species from H. chæretis, while in any case its specific distinctness from the latter is clearly marked.
Apart from the question whether it is advisable to distinguish generically these two species under the name of Lycyana (in regard to which I have considerable doubt), it is clear that H. macrostoma (if the present specimen really belong to it) presents the same relation to H. chæretis in regard to the structure of the lower carnassial as is presented by the striped hyæna (H. striata) to the spotted hyæna
1 Animaux Fossiles et Géologie de l'Attique, pl. xv, figs. 1-5.
of batongedien inom
(H. crocuta); so that we have the same line of specialization going on independent. ly in different groups.
Gazella, sp.—The existence of a species of gazelle is indicated by the distal extremity of a right metacarpus (No. 5) represented in woodcut, fig. 2. This specimen is readily distinguished from the metacarpus of the sheep and
goats by the rounded contour of the lower part of the front of the shaft, as well as by the absence of the deep depressions immediately above the trochleæ on this aspect, and also by the position and direction of the nutrient foramen. It is equally well distinguished from the metacarpus of the Saiga, and likewise from this bone in the deer, in which there is a very deep anterior groove. Compared with the metacarpus of Gazella subgutturosa, there is such a close resemblance as to indicate that the fossil bone likewise belongs to a gazelle. It is rather smaller than the corresponding bone of G. subgutturosa, and would thus agree
better with that of the somewhat larger G. gutturosa, with Fig. 2. Anterior as. Whi
which I have been unable to compare it. Since, however, pect of the distal extre. all the other Chinese fossil mammals appear to belong to mity of the right metacarpus of Gasella, sp.;
extinct species, it is probable that the same will hold good for from Mongolia, 1
the gazelle, although I do not intend to propose a new name
for it. It is probable that the distal extremity of the left humerus (No. 4), as well as the imperfect distal portion of the right radius (No. 6), belonged to the same individual as the one which owned the matacarpus. Of two fragments of horn-cores (No. 7) the longer is compressed from side to side after the manner of modern gazelles, and probably belongs to the species under consideration,
No remains of gazelles are described by Dr. Koken among the specimens obtained from Yunnan; neither are there any species of that group living at the present day in China proper. The Mongolian deserts are, however, the exclusive home of Gazella gutturosa, and it is, therefore, especially interesting to find a predecessor of that species in our collection. So far, indeed, as they go, these specimens serve to confirm the correctness of the locality assigned to the collection, and indicate the prevalence of desert conditions in Mongolia since the Pliocene. Indeed, the whole series of specimens belongs to groups of animals, viz., hyænas, gazelles, oxen,' and horses, of which at least some living representatives are confined to more or less completely desert regions.
Bos, sp. Among the Yunnan collection Dr. Koken has figured teeth referable to the genus Bos, in its wider sense, and it is therefore highly probable that the specimens Nos. 3, 4, should belong to the same genus.
Equus sivalensis, Falc. and Caut. In my description of the remains of this species from the Siwaliks? I came to the conclusion that its affinities were closest with the Kiang (Equus hemionus) of Tibet and Mongolia, although the upper cheek-teeth are distinguished by the smaller antero-posterior length of the
1 The Yak inhabits the desert-like Tibetan plateau. Palæontologia Indica, ser. 10, vol. ii, p. 92.
anterior pillar of the premolars, and the larger size of the first tooth of that series. In India the species is unknown westward of the Jhelum. As regards its dental characters E. sivalensis occupies a position intermediate between E. stenonis, of the European Pliocene, and the modern representatives of the genus.
In the memoir cited (pages 77-78, pl. vi, figs. 14, 15), Dr. Koken described and figured a rightfourth upper premolar and third molar of an Equus from Yunnan. The premolar is stated to be very like the corresponding tooth of E. sivalensis, but distinguished by the smaller development of the posterior valley and the thinner coating of cement. The molar is distinguished by the greater depth of the same valley, and the greater plication of the enamel. The resemblance of both teeth to those of the Kiang is mentioned.
Of the equine remains from Mongolia, I shall only notice the two teeth, of which the crowns are figured in woodcut, fig. 3. Both the teeth (which are more or less damaged) belong to the right side, and are in a medium condition of wear. The one represented as a (which is the more worn) is the fourth premolar, while the other (6) is the third molar. The latter is im perfect posteriorly, and indicates a smaller animal than the one to which the former belonged.
There can be no hesitation in regard. ing these teeth as specifically identical with those figured by Dr. Koken. The premolar has, however, a deeper posterior valley (the notch immediately to the left of hy), and thus shows that the size of this valley is of no specific importance, varying to some extent with the degree of wear. In the molar the plication of the
enamel of the central islands is less than Fig. 3. Crown surfaces of fourth right upper in the Yunnan example; but I attach very premolar (a), and third molar (6) of Equus sivalensis; from Mongolia. t. p. anterior little importance to such variations. The pillar; hy posterior do.
cement of the premolar is thick. Compared with the corresponding teeth of the upper jaw of E. sivalensis, figured in the “Palæontologia Indica,” ser. 10, vol. ii, pl. xiv, fig. 1, an almost exact identity will be found; and I have accordingly no hesitation in referring both the Mongolian and Yunnan teeth to that species.
Bearing in mind the relationship which I have seen reason to believe exists between E. sivalensis and the living E. hemionus, it is of considerable interest to be thus able to trace the range of the former into the very area occupied by the latter. Since, moreover, we have no evidence of the occurrence of E. sivalensis in the Western Punjab, it may be suggested that E. onager of Baluchistan, Kach, and Persia may possibly have had a different origin, and is not, therefore, specifically the same as E. hemionus, although the two are practically indistinguishable.
Described in the text as left, but figured (unless reversed) as right.
Further note on the Darjiling Coal Exploration, by P. N. Bose, B.Sc.,
F.G.S., Deputy Superintendent, Geological Survey of India. The possibility of coal seams, similar to those of the Lisu-Ramthi area, being found in the Damuda ground west of the Tistá; the proximity of this ground to several existing lines of cart and one line of railway-communication with the plains; and the fact that a considerable balance was left from the grant made during the previous season by the Government of Bengal, were considerations which led 10 the continuance of the coal exploration.
The entire Damuda area between Pankhabári and the Tistá was examined in some detail, and special attention was paid to the ground just by the Tista Valley cart-road.
The modus operandi of the exploration being similar to that of the previous season need not be detailed again; and as the pits sunk disclosed no promising seams, the details with regard to them will probably serve no useful purpose. A few sections, however, bearing upon the geology of the area, are given in the following notes, which must be taken as supplemental to the systematic treatment of the subject by Mr. Mallet in Memoirs, Volume XI, Part I. The economic result, though disappointing, is not without importance, as the question of the finding of workable seams in the area explored, which crop up from time to time, may now be safely said to be set at rest.
(a)-The Tistá Valley Cart-road Section. At and a little above Sivok (which is situated at the debouchure of the Tistá into the plains), the Tertiary sandstones are soft, fine grained, highly micaceous, and have a rather low south-western dip. Pockets of lignite were found in them just by the cart-road. On the east side of the Tista also the river section exposes similar sandstones with south-eastern dip, overlaid by very coarse recent deposits. The lowness and the southern direction of the dip are noteworthy, and will be referred 10 when we come to discuss the important question of the elevation of the Himalayas.
The inclination becomes northern about a mile north of Sivok. It still continues rather low for some distance; and soft, massive, fine-grained, micaceous sandstones still form the chief rock.
Just south of the Andera Jhora, and close to its junction with the Tistá, massive conglomeratic sandstones are encountered. They are also seen on the opposite bank of the Tista with a rather high north-western dip. These conglomerates apparently form the top of the Tertiary system, as they do in the area further eastward. They are succeeded to all appearance without a break by shales and sandstons, which, however, have a Damuda facies about them.
Further north, thin seams of coal are seen by the Tistá close to the cart-road. A rather low, south-eastern dip is observable in them, though somewhat in distinctly. On the south side of the Ruyem or Kali Jhora a great thickness of crumbly earthy rocks with carbonaceous shales and thin seams of coal, the whole resting upon sandstones and having a distinct southern dip, is met with. These rocks are continued in a south-western direction along the strike to the head of the Kali Jhora, where an immense slip affords a grand view of them. The slip has affected a large