391 



Fig. 2. Alveolar border : c, the orifice of the dental canal. 



Fig. 3. Inside view : a, the inflected angle ; c, the orifice of the dental canal. 



Fig. 4. Fractured surface of the ramus: c, dental canal; d, part of an 



alveolus. 

 Fig. 5. Lower border of the jaw, showing a, the inflected angle. 

 Fig. 6. Outline of the crown of the last molar tooth, natural size. 



PLATE X. 



Fig. 1 . Upper view of the astragalus of, probably, a species of Nototherium 

 (see No. 1509.) : a, outer or fibular division of the upper articular sur- 

 face ; b, inner or tibial division ; c, scaphoid articular convexity conti- 

 nued from the tibial surface ; d, rough depression, partially dividing 

 the tibial from the scaphoid surface. 



Fig. 2. Under view of the same astragalus : e, flat calcaneal surface ; /, part 

 of the surface corresponding with a prominence on the os calcis ; g, de- 

 scending process of the articular surface corresponding with a depression 

 on the os calcis ; c, scaphoidal convexity. 



Fig. 3. Upper view of the astragalus of the Wombat. 



Fig. 4. Lower view of ditto: the same letters indicate the same parts as in 

 the figures of the gigantic analogue of this singularly formed bone. 



Fig. 5. Inside view of the os calcis of, probably, the Diprotodon aiistralis 

 (See No. i486.) : a, calcaneal prominence for the attachment of the 

 tendo achillis ; b, an obtuse process from the inner and under part of the 

 bone ; d, the tendinous groove on the inner side of the bone ; e, the as- 

 tragalar articular surface ; g, the depressed portion of that surface corre- 

 sponding with the prominence, marked^, in Fig. 2. 



Fig. 6. Outside view of the same os calcis ; showing c, the tendinous perfo- 

 ration on the outer part of the base of the calcaneal process a ; /, the 

 cuboidal concave articular surface. 



Fig. 7 '. Upper surface of the same os calcis. 



Fig. 8. Under surface of the same os calcis, showing the wide tendinous 

 groove continued from the perforation. 



