174 



ANIMAL BIOLOGY. 



[Part I. 



The Hind Limb. The typical hind limb (Fig. 57, A.) consists 

 of the following parts : (1) a single proximal bone articulating at 

 the acetabulum, the femur (F.) ; (2) two bones side by side in the 

 crus, one pre-axial, the tibia (Ti.), and one post-axial, the fibula 



FIG. 57. RIGHT HIND LIMB. 



A. Typical. B. Tarsus of rabbit. C. Distal part of hind limb of fowl. 

 F. Femur. Fi. Fibula. Ti. Tibia. 



ce. Centrale. dl. Digits, fi. Fibulare. in. Intermedium, m.t. i.-iv. Meta- 

 tarsals. t. i.-v. Tarsals. ti. Tibiale. 



(Fi.) ; (3) the tarsus, composed of nine bones (a.) a proximal row 

 of three bones, tibiale (&), inter-medium (i), &nd fibulare (fi.) ; (b.) a 

 single bone, the centrale (ce.\ between the proximal and distal 

 rows ; (c.) a distal row of five tarsalia, numbered from the tibial to 

 the fibular side; (4) the metatarsus (mt.) 9 composed of five meta- 

 tarsals ; and (5) the five digits with their phalanges. The 

 student cannot fail to notice how marked is the apparent 

 homology of the parts of the fore and hind limbs, femur answer- 

 ing to humerus, tibia to radius, and so on. 



In the rabbit the femur is a strong bone, with rounded 

 head, borne upon a neck, below which is the lesser trochanter, 

 and above which is the strongly-marked greater trochanter, 

 overhanging a trochanteric fossa. A third trochanter is on 



