XV. ] INS EC Tl VOU A. 249 



this is present in the Common Seal (Phoca vitulind). 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 

 (Ertnaceus) there is no supracondylar foramen in the 

 humerus, but a large supratrochlear perforation. In Cen- 

 tetes, Rhynchocyon, and nearly all the other genera, there 



»a supracondylar foramen. 

 The radius and ulna are generally completely developed 

 and distinct ; but in Galeopithecus, Macroscelides and Petro- 

 droj/ius, they are fused together inferiorly. 



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

 traordinary form, being very short, and extremely broad 

 and flattened at both extremities, though contracted in the 

 middle. In addition to the narrow oval head for articulation 

 with the glenoid cavity of the scapula, there is a larger 

 saddle-shaped surface, which articulates by a separate syn- 

 ovial joint with the outer end of the coraco-clavicle. The 

 deltoid ridge is very prominent, joining the inner tuberosity 

 above. From each condyle a slender bony process extends 

 upwards. There is a supracondylar foramen. The ulna has 

 a greatly developed olecranon, with a narrow keel behind, 

 and expanded laterally at the extremity. 



In the Cape Golden Mole. (Chrysochloris) the humerus 

 is much more slender generally than in the true Moles, but 

 the inner condyle is extremely elongated. The olecranon 

 is long, narrow, and incurved. The fore-arm has a third 

 bone, extending from the palmar surface of the carpus 

 almost to the elbow, where it has a free termination. This 

 appears to be an ossification in one of the flexor tendons. 



I The Chiroptera have a long slender humerus, having a 



