The Skeleton 87 
of a division into two articular surfaces. The 
ventral side of the femur near the proximal end 
shows a fairly distinct trochantal ridge. 
The shin or crus is made 
up of two well-developed 
bones, the ¢zbia (t) and fib- 
ula (fb), the former being 
somewhat longer and con- 
siderably thicker than the 
latter. 
The tibia consists of a 
cylindrical shaft with en- 
largements of about equal 
size at the ends. The 
proximal end forms most 
of the knee joint, the 
distal end articulates with 
a tarsal element said by 
Reynolds to represent the 
fused astragalus and cen- 
trale, by Wiedersheim 
called the astragalus, and 
said to represent the 
united tibiale, interme- 
dium, and centrale (tb, 
Fic. 29. Posterior Lime. 
ca, calcaneum or fibulare; cl, claw; 
f, femur; fb, fibula; ¢, tibia; 
43, 14-5, tarsalia; tb, 1b', tibiale- 
centrale; 1V, V, 4th and 5th 
metatarsals. 
tb’). The fibula articulates by a small enlargement 
at its proximal end with the femur, and by an enlarge- 
ment of about equal size, at its distal end, with the 
fibulare or calcaneum (ca), and with a small facet on 
the above-mentioned tibiale-centrale element. 
