490 



The tuberosities, and especially the outer one (Plate CXIII. figs. 1 & 2, c), are less 

 produced beyond the head (a) than in Osphranter rufus; and in this respect the fossil 

 conies nearer to Mao', major. 



The deltoid ridge, continued down from the outer tuberosity, is much more produced 

 from the shaft, throwing the surface (g) more to the outer aspect than in the recent 

 species. The rounded angle of the shaft leading to the ridge (e) in Osphranter rufus 

 and Macropus major is less marked in the fossil. 



The long persistence of the epiphysial suture (t) at the proximal end of the humerus 

 in Macropodida , as exemplified in the full-grown and dentally mature Macropus major 

 and Osphranter rufus (Plate LXIX.), is also shown in both the preceding and the 

 present humeri of the extinct species, of which the subjects of Plates CXI. and CXII. 

 doubtless give the full size of the humerus in those species. 



To limit the predication of maturity to the obliteration of such epiphysial suture 

 would be, in my opinion, incorrect in the Macropodidce ; the epiphysial state of the 

 proximal end of the humerus is retained far on into the " procreative " stage or period 

 of existence of such Marsupials. 



§ 7. Macropodidce (Humerus). — Amongst the more fragmentary evidences of Macro- 

 podal humeri may be noted a shaft which shows less robust proportions than the last- 

 described fossil, but it must have been at least of equal if not greater length. From 

 the end of the deltoid process, for example, to the entepicondylar canal is 3 inches 

 1 line, the same admeasurement in the subject of Plate CXII. giving 2 inches 6 lines: 

 the breadth of the fragmentary shaft below the deltoid process in 1 inch 2 lines ; in the 

 entire humerus it is 1 inch 3 lines ; in Macropus major it is 8 lines, as in Osphranter 

 rufus. 



The transverse extent of the distal articular surface (Plate CXIII. figs. 4, 5, 6) is 

 greater than in the subject of Plate CXII. 



The broken fossils show the usual proportion of the medullary cavity in the shaft of 

 the humerus. 



In a general way the humeri may be. ranged into a thicker- and a thinner-shafted 

 series, the length and size of the bone varying in both. 



In one of the slender-shafted large humeri the deltoid ridge is more prominent, and 

 the surface leading to the pectoral ridge slopes more backward. In another of this 

 series the pectoral ridge is continued upward or proximad, dividing a tract of the 

 shaft into two well-marked facets ; in a third fossil the corresponding tract or surface 

 of the humeral shaft is undivided. 



There are minor characters indicative of almost as many large species of Macropodidce 

 as have been defined by the jaws and teeth. Unfortunately the haphazard way in which 

 those fossils have been drifted along the present river-beds precludes the possibility of 

 associating unequivocally the limb-bones with the maxillary and dental fossils. 



It may, most probably will, be the work of succeeding palaeontologists to complete the 

 restoration of the skeletons of the extinct Macropodidce ; but I refrain from multiplying 



