E. (LOXODON) MEEIDIONALIS. 115 



jaw, although still young, comprising the right ramus, with 

 the remains of the second milk molar in front, and the 

 empty alveolus of the antepenultimate true molar behind. 

 The age of the interposed third milk molar is therefore very 

 pointedly indicated. The crown presents eight principal 

 ridges, with front and back talons. The four anterior ridges 

 alone are affected by wear — the first showing two distinct, 

 curved and reniform discs, with the convexity in front ; the 

 second, three continuous but separate discs ; the third, four ; 

 the fourth barely abraded, but exhibiting the rings of five 

 digitations. The tooth, in its longitudinal direction, has the 

 usual curve, being concave on the outer side. The ridges 

 are wide apart, and enwrapped by an enormous layer of 

 cement, very much as in the young teeth of E. (Loxod.) pla- 

 nifrons. In its general form, the crown differs notably from 

 the second milk molar, in presenting a nearly uniform width 

 from front to rear. There is no. indication of plication in 

 the enamel of the plates, nor any outlying mesial loops. The 

 specimen is hard and heavy, resembling in its mineral con- 

 dition the hard Sewalik fossils when a little weathered. The 

 dimensions of the tooth are : — 



Length of crown, 4'6 in. Width of ditto at first ridge, 1*6 in. Width of ditto 

 at fifth ridge, l - 8in. 



Another very fine detached specimen of the last milk 

 molar, lower left, with the first four ridges worn, shows also 

 eight principal ridges, besides talons. Posteriorly it is de- 

 nuded of cement ; the ridges are wide apart, and the enamel 

 very deeply grooved, as in Crag specimens, the grooving 

 being strongly marked below, and disappearing towards the 

 apices of the ridges. Hence a corresponding difference in 

 the edging of the enamel-plates, according to the stage of 

 detrition. This specimen is very ferruginous, and might 

 pass for a 'Crag' fossil. The dimensions are : — 



Length of crown, 4'7 in. Width at first ridge, 1-5 in. Width at fifth ridge, 1:85 

 in. Height of enamel-plate at fifth ridge, 2-3 in. 



Another smaller-sized detached specimen of the same 

 tooth shows only seven principal ridges, with front and back 

 talons, proving that there may be a difference of one ridge, 

 more or less, in the ridge-formula of the last lower milk 

 molar. Taking the data furnished by the young jaws, upper 

 and lower, and using a? as a symbol for the talons, the ' ridge- 

 formula' of the milk-series in E. (Loxod.) meridionalis is 

 proved to be thus : — 



Milk molars. 

 x3x + x6x + x8x_ 

 x3x + xQx +• xSx 



This specimen is also very ferruginous and ' Crag '-looking. 



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