i ;o 



ANIMAL BIOLOGY. 



[Part I. 



with the aid of the figure, in which sp. is the crest or spine 

 which forms the acromion border ; gl. b. is the glenoidal border; 

 gl. c. the glenoidal cavity ; co. b. the coracoid border ; 5. sc. b. the 

 supra-scapular border, which is postero-dorsal in position. 



In the Fowl the coraeoid is a separate bone (54, E., co.). The 

 glenoidal cavity (gl. c.) is at the junction of coracoid and 

 scapula (sc) ; h. co. is the head of the coracoid which articulates 

 with the sternum by a. st. The clavicles are represented by the 

 merry-thought or furcula (/.), of which the flattened median 

 portion (h. cl.) is called the hypodeidium. 



The Fore Limb. The typical fore-limb consists of the follow- 

 ing parts : (1) a single proximal bone in the arm, the humerus 



u. 





FIG. 55. EIGHT FORE-LIMB, 



A. Typical. B. Fore-limb of fowl. C. Humerus of rabbit. D. Radius 

 and ulna of rabbit. E. Carpus of rabbit. 



H. Humerus. R. Radius. U. Ulna. c. Centrale. ca. Carpus, cap. Capi- 

 tellum. di. Digits, g. t. Greater tuberosity. h. Head of humerus. i. In- 

 termedium. 1. t. Lesser tuberosity. TO. ca. Metacarpals. me. i. ii. iii. Meta- 

 carpels of fowl. o. /. Olecranon fossa, ol. pr. Olecranon process, ph. i. ii. 

 iii. Phalanges of fowl. r. Radiale. sh. Shaft, sy. c. Sigmoiclal cavity, tr. 

 Trochlea. u. Ulnare. 



(Fig. 55, A., H.); (2) two bones side by side in the fore-arm, 

 one pre-axial the radius (Pi.), and one post-axial, the ulna (U.); 

 (3) the carpus, composed of nine bones ; (a.) & proximal row of 

 three bones, radiate (r.), intermedium (i.), and ulnare (u.) ; (b.) 

 a single (sometimes double) bone, the centrale, between the 



