94 FOSSIL JAWS OF MACROPODID.E, 



The lower premolar (PL xvi. fig, 1) before eruption simulates 

 remarkably well the ledged upper tooth in several Macropods. 

 The intero-posterior ledge-like cusp occup3dng half of the outer 

 side is separated from the lobe posteriorly by a wide cleft, but 

 within which a larger and a smaller oblique fold ascend on the 

 inner side of the cusp; anteriorly the cusp joins the lobe by the 

 incurving of its sharp edge, and anterior to this transverse sepi- 

 ment are two cavities separated by a deep rib which ascending to 

 the crest meets a corresponding one on the inner side of the 

 crown, and with it forms a pronounced denticle on the crest. In 

 the worn tooth (PI. xvi. fig. 4) the structure is still recognisable. 



Examples — eleven t. 



Mandibular. — An adolescent right ramus with all the cheek- 

 teeth and with the incisor nearly entire (11126); accessory pro- 

 cesses well marked — A right ramus with all the cheek-teeth but 

 p.^ perfect (11119); remains of the accessory processes distinct; 

 aged — The associated rami of an aging mandible (8876), with the 

 greater jDart of the ascending limljs; accessory processes as before 

 — Portion of a right ramus with the last three molars (8873), 

 adolescent — Alveolar portion of a right ramus with all the teeth 

 mutilated but m. ^, m. - (10409); processes nearly obsolete from 

 wear; aged — Portion of a right ramus with the last three molars 

 (10597); processes very distinct; adult — An adolescent right 

 ramus with incisor and all the cheek-teeth but m.^, which has 

 been broken off (11132); processes as before — A right ramus from 

 a suckler with mp.* and m." in its crypt; the exposed socket 

 of the incisor showing that it was procumbent (10226); the 

 processes on mp.* well marked — Fragment of a left ramus with 

 m.^j m.^, and part of m."^ (10596); processes as before; young — 

 Both rami of an aged example all the teeth al^sent but the last 

 three molars of the left side (11306). 



Sthenurus pales, n.s. 



Longitudinal links reduced to a tumescence on the floor of the 

 mid valley and adjacent base of the fore lobe. Posterior basal 



