468 



The bony palate (Plate XCVII. fig. 1) loses a little breadth behind the incisive 

 foramen (a), then expands with an outward curve to the sockets of the premolars (p »), 

 A mid tract of the breadth of the incisive foramen is continued backward as a very 

 shallow channel to opposite the third grinder (m 1), where the uniform level of the bony 

 palate is gained. A similar but rather deeper channel is continued forward from the 

 fore part of the incisive foramen, and slightly expands to its termination at the outlets of 

 the mid incisors (i 1). The intermolar tract of the bony palate is less concave longitudi- 

 nally than in Macropus and Osphranter, and less so transversely than in Macropus 

 major. Osphranter more resembles Palorchestes in this direction. 



There is no trace in Palorchestes of the pair of small oblong holes where the palato- 

 maxillary suture (ib. ib. 20) begins to bend backward near the socket of the last molar. 

 In Palorchestes this suture describes a less angular, more semicircular course than in 

 existing Kangaroos. The hind border of the bony palate appears to have been more 

 concave than in Macropus major or Osphranter robust us, in which respect it resembles 

 more some of the Halmaturi. A pair of small vascular foramina, 1 inch 3 lines 

 apart, occur at the interval between the right and left premolar (p 3 ). 



The anterior pier of the zygoma (Plates XCVL, XCVII., CV., CVII.,si»)is subtrihedral, 

 the hind surface or side being the broadest, nearly flat vertically, concave transversely. The 

 fore part is subequally divided into an upper and lower facet by a forwardly directed 

 rounded angle. A narrow semicircular notch (Plate XCVI. fig. 1, 0) at the upper 

 part of the base of this pier indicates a part of an orbit relatively smaller than in the 

 Kangaroos. Above and in advance of this notch is the ectorbital aperture of the 

 lacrymal canal characteristic of the Marsupialia. There does not appear to be, in 

 either side of the skull, a trace of an antorbital foramen ; but I incline to believe in 

 6ome accidental obliteration of that issue, rather than that it never existed. 



Each molar series describes a slight curve convex outward. The base of the broken 

 crown of the premolar is subelliptic (Plate XCVII, fig. 1,^3), 7-g lines in long dia- 

 meter, 6 lines in transverse diameter, which is at its middle ; it is not broadest behind 

 as in most other Kangaroos ; the inner side is more convex than the outer one. The 

 6econd molar (ib. ib. d 4) is bilophodont, with a prebasal ridge ; a fold of enamel (ib. /') 

 indicative of the ridge remains on the inner side ; the rest of the ridge is lost in the con- 

 tinuous hollow tract of dentine occupying the base of the worn-down anterior lobe (a). 

 Opposite folds of enamel, the inner one the longer, indicate the interlobal valley ; the 

 dentine at the base of the link (/') leads across from the anterior to the posterior field 

 of attrition. The third molar (ib. ib. m 1) has been worn down to the same degree. In 

 both these molars the inner side of the basal part of the front lobe (a) encroaches 

 further than that of the hind lobe (b) upon the bony palate, forming the origin of a very 

 strong antero-internal root. In the fourth molar (m 2) and in the last (m 3), the corre- 

 sponding root makes a projection beyond the inner side of the hind lobe of the tooth in 

 advance. The base of the mid link (r) remains in m 2 ; in m 3 that link shows a median 

 notch. More of the narrow prebasal ridge (f) is apparent in the last two teeth. The 



