xv.] MARSUPIALIA. 279 



and with strongly developed deltoid and supinator ridges 

 (see Fig. 84, p. 242.) These characters prevail generally 

 throughout the order, though in a less marked degree. The 

 supracondylar foramen is almost always present, some of 

 the Dasyures being exceptions. 



The radius and ulna are always distinct and well-developed 

 bones. The upper end of the radius is small and rounded, 

 and more or less rotation is permitted between the bones, 

 even in the carnivorous forms. 



In the animals constituting the order MONOTREMATA, 

 the humerus is something like that of the Mole, short and 

 extremely broad at both extremities, with greatly produced 

 inner and outer condyles, though contracted at the middle 

 of the shaft. 



The radius and ulna are stout, and rather flattened at the 

 lower end, where they are of about equal size, and closely 

 applied together. The upper end of the olecranon is 

 widely expanded laterally. 



