4 FAUNA ANTIQUA SIVALEXSIS. 



tion of the intennediate type of a proboscidean molar tooth, from which 

 those of the other species diverge in opposite directions. It belongs to 

 the Mastodon Elephantoides of Clift. The dark granulated shade 

 below the portion of the ivory nucleus sustaining the five posterior 

 ridges indicates the hollow of iheir common fang, which in the fossil is 

 occupied by a core of sandstone. — B.M. 



Length of tooth, 10 - 3 in. 



Fig. 6 b. — Eleplias insignis. Vertical section of anterior portion of 

 adult tooth of lower jaw. The two front ridges only have been touched 

 by wear. The ivory, enamel, and cement present the same characters 

 as in the upper molar, but the common curve of the crown is slightly 

 concave instead of convex. The posterior part of the basal portion of the 

 pulp nucleus has not completed the stage of calcification, its place being 

 occupied by a nest of calcareotis crystals. The figure also shows two 

 ridges of the preceding molar, with their common fang implanted in 

 the loAver jaw. — B.M. 



Plate III. 



Fig. 7 a. — Eleplias Ganesa, a fossil Indian species. Vertical section 

 of last upper molar. The crown consists of ten principal ridges, with a 

 subordinate talon ridge in front and behind. The anterior seven ridges 

 have their summits worn. A small portion is broken off at the anterior 

 end. The disposition and relative proportions of the ivory, enamel, 

 and cement bear the closest resemblance to those of the corresponding 

 tooth of E. insignis, and the number of ridges agrees. In fact, there are 

 no good characters by which the teeth of these two species can be 

 satisfactorily distinguished, although the crania are so remarkably 

 different.— B.M. 



Length of tooth, 9-25 in. 



Fig. 7 b. — Eleplias Ganesa. Vertical section of posterior molar of 

 lower jaw. A small portion of the anterior end of the crown has been 

 broken off, but the presence of the anterior fang proves that the section 

 includes the whole length of the tooth, except the first ridge, the 

 posterior end being entire. It appears to have consisted of eight prin- 

 cipal ridges, with a talon ridge behind, and a subordinate ridge in front. 

 Five of the ridges have been in use, the anterior two being worn down 

 close to the common base of ivory ; the three last ridges are entire. It 

 bears a close resemblance to the corresponding inferior tooth of E. 

 insignis in the form of the ridges, thickness of enamel, and proportion 

 of cement. — B.M. 



Fig. 8.— Mastodon latidens (Clift). Vertical section of two last 

 molars of upper jaw. The specimen of which the section was made 

 was formerly in the collection of the Geological Society, and is figured in 

 C lift's memoir (Plate XXXVII. fig. 1). The last tooth shows five prin- 

 cipal ridges with a posterior talon ridge and a subordinate ridge in front. 

 The ridges are transverse and divided by a longitudinal cleft into two 

 pairs of principal points without intermediate mammilla? in the hollows. 

 The enamel is rery thick and the cement is reduced to a thin layer, 

 only observable in the bottom of the hollows. The ivory lobes resemble 

 those of E. Ganesa, but are less elevated, with a broader base. The 

 anterior tooth had been a long time in use, and the ridges are nearly all 



