274 THE ARM AND FORE- ARM. [CHAP. 



is much curved forwards. The deltoid ridge is strong, and 

 extends far down on the bone, especially in the Bears. The 

 inner condyle is prominent. The anconeal fossa is deep. A 

 supracondylar foramen exists in the FelidtE, and in most of 

 the Viverridce, Mustelidce, and Procyonidce, but not in the 

 Canidce, HycEtiida, or Ursidtz. 



The radius differs from that of Man, inasmuch as its 

 upper end is broad, flattened, and extends further across the 

 front of the humeral articular surface, forming part of the 

 hinge (see Fig. 88) ; and although it is never ankylosed with 

 the ulna, scarcely any appreciable amount of movement is 

 allowed between them. The ulna has a large compressed 

 olecranon, and a shaft gradually tapering to the lower 

 extremity. 



In the Pinnipedia the bones of the anterior limb are very 

 short and stout. The humerus has a remarkably prominent 

 deltoid ridge, and usually no supracondylar foramen, though 

 this is present in the Common Seal (Phoca vitulina). The 

 upper end of the ulna, and conversely the lower end of the 

 radius, are much expanded. 



In most of the INSECTIVORA the bones of the arm gene- 

 rally resemble those of the Carnivora. In the Hedgehog 

 (Erinaceus) there is no supracondylar foramen in the 

 humerus, but a large supratrochlear perforation. In Centetes 

 Rhynchocyon, and nearly all the other genera, there is a 

 supracondylar foramen. 



The radius and ulna are generally completely developed 

 and distinct ; but in Galeopithecus^ Macroscelides and Pctro- 

 dromus, they are fused together distally. 



The Mole (Talpd) and its allies have a humerus of ex- 

 traordinary form (see Fig. 34, p. 95), being very short, and 

 extremely broad and flattened at both extremities, though 

 contracted in the middle. In addition to the narrow oval 



