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§ 14. Macropus Titan (skull). — The first evidence of this extinct species yielded by 

 any considerable part of the skeleton in addition to the maxillary and mandibular ones 

 is the chief subject of Plates LXXVI.-LXXIX. 



It is a great part of the skull of a Kangaroo, wanting the lower jaw, but including 

 the cranium proper, the interorbital and the hinder part of the facial division of the 

 skull ; also great part of the left zygomatic arch with the included orbit and temporal 

 fossa, the bony palate, and the molar dentition, of which the two hindmost teeth are 

 sufficiently entire to afford the means of specific determination. 



Other projecting parts and processes have suffered fracture, and the region of the 

 large frontal sinuses has been obliquely crushed. 



The specimen is in the usual heavy petrified condition of fossils from the freshwater 

 drift ; it shows the effects of transport and attrition during the movements of this matrix, 

 at the locality now forming the bed of " King's Creek," near Clifton, Darling Downs, 

 Queensland* ; it was picked up by Mr. W. F. Tooth, Jun., at a part of the creek indi- 

 cated by Dr. Bennett as likely to yield fossils when the bed was exposed at the dry 

 season succeeding a flood. As much of the matrix has been cleared away as could be 

 safely meddled with, since it came into my hands, and the present state of the fossil is 

 figured, of the natural size, in Plates LXXVI.-LXXIX. 



According to the Cuvierian precept the molars received the first attention ; and the 

 characters of these in several of the large extinct Macropodidw having been determined 

 and characterized in the foregoing pages, I had helpful subjects of comparison with 

 those in the present skull, which were in an instructive state of preservation. 



The upper molars of Macropus Titan differ from those of Macropus major not only 

 in size, but in pattern. Not, indeed, so much in the general one affecting the transverse 

 lobes, links, and prebasal ridge, as in the sculpturing of the hind surface of the tooth, 

 which is the seat of instructive modifications characteristic of genus and species in other 

 members of the family Macropodidce. 



In Macropus major that surface (Plate LXXIX. fig. 3) is moderately hollowed 

 lengthwise, and thickly coated with cement, which partly fills the triangular transverse 

 concavity, the apex of which shallows to the ordinary level of the hind surface before 

 reaching the base of the crown ; when the cement is removed, the inner enamel boundary 

 (g) is sharper and more produced than the outer one (h). 



In Macropus Titan the enamel, after coating the inner border of the hinder lobe, 

 extends backward, downward, and outward, projecting as a sharp-edged ridge (ib. fig. 2,g, 

 and Plate LXXXI. fig. 18, t), defining a deeper depression on the hinder surface of the 

 tooth. There is also a shallow vertical groove (h) continued from the hind part of the 

 apex of the inner border of the hind lobe downward toward the base of the crown, which 

 groove seems to define the inner limit of the oblique posterior ridge. One sees 

 that this groove repeats the deeper cleft that defines the mid link, internally, from the 



* See " A Trip to Queensland in search of Fossils," by Dr. Geobge Bennett, F.L.S., in Annals & Magazine 

 of Natural History, April 1872. 



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