strongest, and rises an inch or more above the articular cavity of the humerus, it is 

 extended in the axis of the ulna. 



In Perame/es nasuta the first and fifth digits of the hand are almost obsolete, the 

 fourth is short and weak, the second and third are of equal length, and alone appear in 

 the fore foot of the living Chcerqpus, All other Marsupials have a pentadactyle fore 

 paw; in Cheironectes the 'pisiforme' is so developed as to give the appearance of a 

 sixth digit wanting the nail. All the true digits of such paw have so much lateral 

 motion that those on the outer can be opposed to those on the inner side so as to grasp 

 an object. In the Phalangers and Koala the first and second digits are more decidedly 

 opposed to the other three. The modifications of the carpal and other bones of the fore 

 paw will be given in the special osteologies required in the interpretation of the fossil 

 remains which have at present reached me. 



§ 4. The Pelvic Extremities. — The pelvis is composed of the os sacrum, the two ossa 

 innominata, and the characteristic supplemental bones attached to the pubis, called the 

 ossa marsupialia. 



We seek in vain for any relationship between the size of the pelvis and that of the 

 new-born young, the minuteness of which is characteristic of the present tribe of 

 animals. The diameters both of the area and the apertures of the pelvic canal are 

 always considerable, but more especially so in those Marsupialia which have the hinder 

 extremities disproportionately large; in the Wombats also the pelvis is remarkable 

 for its width. The pelvis is relatively smallest in the Petaurists. The anterior bony 

 arches formed by the pubics and ischia are always complete ; and the interspace between 

 these arches is divided, as in other Mammalia, into the two obturator foramina by an 

 osseous bridge continued from the pubis to the ischium, on each side of the symphysis. 



In the Kangaroos, Potoroos, Phalangers, and Opossums the ilia offer an elongated 

 prismatic form ; they are straight in the Opossum, but gently curved outward in the 

 other marsupial genera. In the Dasyures there is a longitudinal groove, widening 

 upward, in place of the angle at the middle of the exterior surface of the ilium. The 

 ilia in the Petaurists are simply compressed from side to side. They are broader and 

 flatter in the Bandicoots, and their plane is turned outward. But the most remarkable 

 form of the ilia is seen in the Wombats, in which they are considerably bent outward 

 at their anterior extremity. In the Kangaroos and Potoroos the eye is arrested by a 

 strong process, given off from near the middle of the ilio-pubic ridge ; and this process 

 may be observed less developed in the other Marsupialia. 



The tuberosity of the ischium inclines outward in a very slight degree in the Dasyures, 

 Opossums, Phalangers, Petaurists, and Perameles ; in a greater degree in the Kangaroos 

 and Potoroos ; and gives off a distinct and strong obtuse process in the Wombats, which 

 not only extends outward, but is curved forward. In the Potoroos the lower part of 

 the ischio-pubic symphysis is produced anteriorly. The length of this symphysis, and 

 the straight line formed by the lower margin of the ischia, is a characteristic structure 

 of the pelvis in most of the Marsupials. 



