465 



the ascending parts of the ramus, is slightly inflected ; a rather wide shallow groove 

 extends above it. The inner surface of the ramus in advance of the inflection is feebly 

 convex vertically. The base of the coronoid process describes a curve convex inward as 

 it extends from before backward. 



The lower border of the left ramus is entire from below (m 1) backward to the hind 

 fracture ; it is obtuse. The thickness or transverse diameter of the ramus, below the 

 middle of m 3, is rather more than four fifths the vertical diameter at that part. Thus 

 the characters of the mandible of the smaller species of Procoptodon are closely repeated 

 in that of the immature specimen of the larger species. 



If the present mandible of Procoptodon Goliah be compared with that of Nototherium 

 Mitchelli in a like state of preservation, which is the subject of Plate XXXVIII., or if 

 a reference be made to that Plate and Plate XLII. {Nototherium inerme), the interesting 

 and instructive modification of the present extinct Marsupial, as transitional between 

 Macropus and Nototherium, will be obvious. But the true macropodal character comes 

 strongly out in the different result of the quest in the substance of the jaw carried out 

 in the subject of fig. 7, Plate XCV. of the present memoir, and in fig. 5, Plate XL. of a 

 Nototherium at a similar stage of immaturity. 



I have been favoured with a photograph of a portion of a left mandibular ramus of a 

 young Procoptodon Goliah at a corresponding stage of dentition (Plate XCV. fig. 5). 

 This was obtained from the Breccia-cave of Wellington Valley ; the original is in the 

 Museum of Natural History of Sydney, New South Wales. 



§ 25. Genus Palorchestes*, Ow. — The finest fossil evidence which has yet reached me 

 of an extinct Kangaroo is the portion of skull figured, of the natural size, in Plates 

 XCVL, XCVIL, CV., CVL, CVII. 



It was discovered in the year 1851 by Dr. Ludwig Becker, "in a bed of yellowish 

 sand and clay mixed with very small shells," in the Province of Victoria, Australia. 

 The matrix had been cleared off before the fossil reached me. 



I am indebted for the opportunity of now describing and figuring this specimen to 

 the kindness and liberality of my esteemed friend and fellow labourer in paleeontology, 

 the late estimable Dr. Kaup, of Darmstadt, to whom the fossil was in the first instance 

 transmitted. 



It is much petrified, heavy, massive, like most of the fossils from the freshwater for- 

 mations of Australia ; but it partakes of the colour of its matrix, which is lighter than 

 that of the fossils from the drift-beds of Queensland. It includes the facial or fore 

 part of the skull with the bony palate and both right and left series of molars. The 

 sockets of the three incisors are preserved in the right premaxillary (Plates XCVL & 

 XCVII. fig. 1, i 1, 2, 3) ; the left has suffered fracture in that part, but the teeth are 

 restored in outline in Plate CVII. 



Comparing the least-worn molar in this skull (Plate XCVII. fig. 1, ni2, and fig. 2, 

 restored) with the corresponding tooth in the upper jaw of Procoptodon (Plate XCIV. 



* rraXatos, ancient; 6p^r)irr>)s, leaper. 



