338 FASCLE 
Blood-supply.—Anterior tibial artery. 
Nerve-supply.—Peroneal nerve. 
B. Prantar Group 
AND MUSCLES OF THE HORSE 
1. Gastrocnemius (Figs. 268, 292, 296).—This muscle extends from the distal 
third of the femur to the point of the hock. 
Shaft of femur 
Fascial band 
Medial head of 
gastrocnemius 
Lateral head of 
gastrocnemius 
Soleus 
Long digital 
flexor Lateral exten- 
sor 
Flexor hallucis 
Tibialis poste- 
rior Tendon of gas- 
trocnemius 
Superficial 
flexor tendon 
Joint capsule 
Medial malle- 
olus 
AV 
Tendon of deep flexor 
Tendon of long 
digital flexor ~ 
Fic. 296.—Muscies or Ricut Lec or Horse; Posterior View. 
It arises by two heads. 
Origin.—(1) Lateral head, 
from the lateral supracondy- 
loid crest (margin of the supra- 
condyloid fossa); (2) medial 
head, from the medial supra- 
condyloid crest. 
Insertion.—The posterior 
part of the tuber calcis. 
Action—To extend the 
hock and to flex the stifle 
joint; these two actions, how- 
ever, cannot occur simulta- 
neously. 
Structure.-—The two bel- 
lies are thick, fusiform, and 
somewhat flattened. They 
are covered by a strong apo- 
neurosis and contain tendinous 
intersections. They terminate 
toward the middle of the leg 
on a common tendon, which at 
first lies posterior to that of the 
superficial flexor, but, by a 
twist in both, comes to lie in 
front of the latter. The deep 
fascia blends with the tendon 
throughout its length, and the 
soleus muscle is inserted into 
its anterior edge. A small 
bursa (Bursa tendinis m. gas- 
troenemii) lies in front of the 
insertion on the tuber calcis, 
and a large bursa (calcanea 
subtendinea) is interposed be- 
tween the two tendons from 
the twist 
middle of the hock. The super- 
ficial digital flexor lies between 
the two heads and is adherent | 
to the lateral one (Fig. 584). 
The term tendo calcaneus or 
tendo Achillis is a convenient 
designation for the aggregated 
tendons in the distal part of the 
leg which are attached to the 
tuber calcis. 
downward to the — 
Relations. Anteriorly, the stifle joint, the superficial digital flexor, popliteus, | 
deep digital flexor, popliteal vessels, and tibial nerve; medially (above), the semi- 
