Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/598

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and less conspicuously along the outside of the base of the lobe a. The middle of the outer concavity of this lobe shows a narrow vertical ridge of the enamel, ending a little behind the apex of the lobe.

In the anterior view of the crown (fig. 9) the convexity of the prominence (o) in the vertical direction is shown, and the degree of inflection of the outer surface inward to form the apex (a') of the V-shaped summit of the antexternal lobe ; the cone (m) simulates in this view an antinternal lobe. The absence of this lobe is characteristic of Chalicotherium ; I do not regard the part of the cingulum (r) as its rudiment, because it is present in the premolars as well as in the molars, and it coexists with the true representative of the antinternal lobe (c) in both Paloplotherium and Anoplotherium (fig. 11, r).

The posterior view of the crown (Pl. XXIX. fig. 8.), in like manner, gives the vertical curve of the dividing bulge, and shows the proximity to the inner side of the tooth of the apex of the lobe b ; the second or postinternal lobe forms the cone d. The inner side of the tooth (ib. fig. 10), formed by the cone m, and the postinternal lobe (d), with the uniting cingulum (r), is much narrower than the outer side ; and the inner division shows consequently a confluence of its roots (t). This molar was implanted by two thick and strong outer roots, and by one larger inner root, composed, as indicated by the inner and outer longitudinal impressions, of two confluent fangs.

With the aid of the pocket-lens the fine transverse striae of the enamel appear, and best beyond the cingulum. The radical cement is rough and thick. The dentine is blanched, not petrified, but has lost gelatine, and sticks like chalk to the tongue, as in the other cave-fossils.

The reader comparing fig. 7, Pl. XXIX., with m 3, fig. 36, pl. 80, of the ' Fauna Antiqua Sivalensis,' fol, or with figs. 5 and 6, a, pl. 7, of Kaup's ' Ossemens Fossiles de Darmstadt,' oblong fol., and with the excellent figure of the upper molar, apparently m 3 of Chalicotherium Goldfussi, in Bronn's ' Lethaea Geognostica,' atlas, fol. taf. xlvi. fig 2, a, may appreciate the grounds for indicating the Chinese Anoplotherioid as Chalicotherium, sinense.

The last molar of Chalicotherium sinense is less than that of Ch. Goldfussi, Kp., and two lines larger in all the dimensions given at p. 431, than is that tooth in Ch. sivalense, Fr. Compared with this, the outer bulge (o) of the antexternal lobe is thicker, more convex vertically, and more produced outwardly. The outer concavity of the postexternal lobe (f'), which in m 3 becomes almost backward in aspect, is less deep in Ch. sinense ; it is angularly indented in Ch. sivalense. The basal ridge (r) between the two inner lobes and that anterior to the base of the mammilloid lobe (m), are relatively less developed in Ch. sinense. The Anoplotherioid character of this lobe, as a large, rather low cone, is well marked. Its summit and the angular margin of the antexternal lobe are worn to the dentine, the exposed tract in the latter being from one to two lines in breadth. The enamel of the anterior part of the ridge of the postexternal and postinternal lobes is abraded, and the dentine beneath, at the fore part of these lobes, is partially exposed. The anterior part of the