PROFESSOR OWEN ON THE FOSSIL MAMMALS OF AUSTRALIA. 
253 
parallel of the interval between the fore and hind lobes of m 3 (Plate XXL fig. 15). 
The retrogression of this buttress of bone is concomitant with the grinding-function now 
assumed by the last of the molar series (compare with figs. 10 & 8). 
The anterior outlet of the suborbital canal (Plate XXI. fig. 16, 21) is 1 inch in advance 
of the anterior border of the orbit. Three lines behind the antorbital foramen is the 
smaller oblique aperture (a) leading down to the interior of the maxillary bone. The 
outer plate of the maxillary, in advance of and below the antorbital foramen, shows a 
depression ; while the maxillary Avail of the nasal cavity swells outward in existing Kan- 
garoos. The proportion of the bony palate preserved shows the small narrow fissure 
where the maxillo-palatine suture bends inward opposite the fore part of m 3 ; elseAvhere 
the palate is entire, as in Macropus proper, in JBoriogale , and Osphranter. The fore part 
of the palate near d 4 shoAvs a longitudinal channel (ib. fig. 15, b), 4 lines broad, bounded 
anteriorly by a ridge, or hind part of the diastema, extending forward and inward from 
the fore part of the socket of d 4, Avhere the sockets (here obliterated) of p 3 and d 3 had 
been. This prepalatal groove is not shown in Macropus major , Macropus rufus, or 
Osphranter robustus. 
The maxillary bone extends for 10 lines behind the last molar, on the level of the 
alveolar openings, and is there impressed by the shalloAV groove leading to the foramen 
and canal between the back part of the maxillary and the pterygoid process of the 
alisphenoid. The figures (Plate XXI. figs. 15-18) being of the natural size preclude 
the need of verbally noting admeasurements. 
The side view of a corresponding part of the upper jaw of a large male Macropus 
rufus , at the same stage of dentition as in the present fossil, is given in Plate XXIII. 
fig. 1 ; it is from one killed by Mr. Gould, and was the largest Kangaroo which he 
saAv in Australia. 
In reference to the constancy in size and other characters of Macropus Titan , I was 
fortunate in finding a second specimen from an adult of this fine extinct Kangaroo in 
the Geological Museum of the University of Oxford, which the learned and estimable 
Professor of Geology, John Phillips, D.C.L., F.B.S.*, liberally transmitted to me for 
comparison and delineation. It was accompanied by an almost entire lower jaw of the 
same species, at the same phase of dentition, and apparently of the same individual. 
Both had been obtained by Dr. Nicholson, of Sydney, New South Wales (now Sir 
Charles Nicholson, Bart.), from the freshAvater deposits of Queensland. 
The subject of figs. 10, 11, & 12, Plate XXII., is part of the left upper jaw with the 
last four molars ( d 4 -m 3) in place ; d 3 and p 3 have been shed and their sockets 
obliterated. The crowns of the remaining teeth show different degrees of abrasion, 
the summits of the last molar being slightly worn, not so as to expose the dentine. 
This specimen, therefore, bespeaks a fully mature but not aged animal. 
The bone includes the base of the anterior pier of the zygomatic arch (from which the 
dependent process has been broken away), part of the floor of the orbit with the orbital 
* His friends and science have to lament an irreparable loss since this was written. 
MDCCCLXXIV. 2 L 
