Ill- 



side of the upper molars. The main lobes have broad convex bases in the side view of 

 the molars (Plate LXXXII. fig. 10), and the entire crown is longer in proportion to its 

 transverse breadth than iu Sthenurus Atlas. 



The front pier of the zygomatic arch (Plate LXXXI. fig. 6, 21') is in advance of the hind- 

 most molar in place (m 2) in this young specimen. The anterior outlet of the suborbital 

 canal (ib. fig. G, 21) is 9 lines in advance of the orbit. Behind the outlet (21) is the small 

 orifice (a) of a (vascular ?) canal, descending into the substance of the maxilla. 1 have 

 not observed this orifice in the large existing Kangaroos. So much of the bony palate 

 ;is is preserved (ib. fig. 8) is entire aud imperforate, as in Macropm major. This cha- 

 racter, associated with the small size and simple structure of the premolar, and, as will 

 be seen in subsequently described fossils, its comparatively early loss, support a reference 

 of the present large Kangaroo to the genus Macropus, as restricted by most zoologists 

 of the present day. 



In the specimen from the Breccia-cave, Wellington Valley, of the left upper maxilla 

 and molar series (ib. fig. 10) the premolar had risen into place ; the last molar (m 3) was 

 protruding from the formative cell, but had not come " into line ; " the first two deciduous 

 molars had been shed. 



The crown of the foremost tooth was broken off, but the fangs remained (ib.^> 3). They 

 were two in number (the hindmost the largest), corresponding in relative size, degree of 

 divarication, and extent of jaw occupied by their insertion w r ith those developed in the 

 unprotruded premolar of the younger specimen (ib. fig. 6,p 3). The choice of the tooth 

 belonging to the fangs in front of the series in the subject of fig. 10 lies between^ 3 and 

 <l b ; but the latter tooth has, in conformity with its broader bilophodont crown, four 

 roots, each pair diverging from a transversely extended base. The evidence of the roots 

 remaining in the socket of the broken molar is therefore decisive of its homology ; 

 the loss of the crown of p 3 is nevertheless regrettable. Its working-surface would have 

 contrasted with that of the tooth d 4, which, having been longer in place and use, 

 shows each transverse lobe worn to near its base, exposing corresponding broad 

 tracts of dentine united by a linear strip along the base of the mid link. In m 1 

 the dentine exposed on the transverse lobes is a linear tract, rather broader on the front 

 lobe ; the front (s) and mid (r) links show abrasion, but not carried to the exposure of 

 the dentine. In m 2 the enamelled summits of the ridges are slightly abraded ; m 3, as 

 before stated, had not risen into place. 



The molar characteristics of the species {Macropus Titan) are well exemplified in this 

 cave-specimen. Sufficient of the palate is preserved to show, as in the preceding one, 

 that it had no large vacuities. The relative position of the zygomatic pier (21) 

 seems to have retrograded as compared with fig. 8, Plate LXXXI. ; but it still strengthens 

 the jaw where the hindmost molar here (m 2) was in use ; when m 3 comes into place 

 and takes its share, the jaw 7 , as we shall see again, becomes concomitantly modified. 



The specimen described and figured formed part of the collection of duplicate fossils 

 obtained, under the favourable circumstances detailed in pp. 135 & 239, by Professor 



