Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/594

 species of larger size. The Chinese Rhinoceros, in this respect, seems to have agreed with the two-horned kind of Sumatra, but to have had a different pattern of upper molar.

The lower molars from the cave of Chung-king-foo, of which there are parts of four, sufficiently exemplify the generic modification of Rhinoceros, but are too few and too much worn and mutilated for worthy evidence of specific distinction. I believe myself justified, from the characters of the upper molars, and the results of the comparisons above detailed, in indicating the Chinese Rhinoceros as Rh. sinensis, Ow. The enamel is, in most parts, smooth and not thick; it retains the natural colour; and the dentine, of chalky whiteness, is absorbent from loss of the soluble constituent, and not otherwise altered.

The main characteristics of the upper molars of this extinct species are evenness of depth of the main valley, its encroaching promontory thick and simple, unusually good indications on the outer enamel-wall of the two lobes (a, b) composing the thick continuous outer tract of dentine which is the characteristic of the present genus of Perissodactyle.

Considering remoteness of position, and the evidence pointing to still greater remoteness in geological time between the present and other known fossil Asiatic Rhinoceroses, I should have been more surprised to find identity of species, than to detect the indications of diversity which have above been noted.

Tapirus sinensis, Ow.

To the genus of Tapir are referable three molars of the upper, and four of the lower jaw. They resemble the other fossils from the Chinese cavern in colour and chemical composition ; the dentine and portions of jawbone adherent to the fangs of the teeth are blanched and absorbent from loss of animal matter, but not mineralized.

Of the existing species of Tapirus these teeth most resemble those of the Sumatran kind (T. malayanus, Raffles, T. indicus, Cuv.). In the upper molar series there are modifications of grinding-surface which help to define the position in that series of such detached teeth.

The tooth, Pl. XXVIII. fig. 8, resembles the third or the fourth premolar in the degree of equality of the rear (b, d) with the front (a, c) half of the crown, and in the smaller proportion of the antexternal tubercle (r) of the cingulum; it more resembles the third premolar in the extension of the cingulum at the rear of the crown (r) to the inner end of the base of the postinternal lobe (d), such rear portion of the cingulum not being bent up to the apex of that ridge as in the last premolar and in the true molars of Tapirus indicus.

Compared with the tooth of the Sumatran species, with which it is homologous, this penultimate premolar of the Chinese Tapir is larger, and has a proportionally greater transverse diameter, or from without inwards; it is still larger than in the European fossil species.