326 FASCL#& AND MUSCLES OF THE HORSE 
opposite muscle. Its direct attachment to the ventral surface of the pelvis is not 
so extensive as a superficial inspection would suggest. The tendon of origin pre- 
sents anteriorly a foramen for the passage of the external pudic vein. The belly 
is composed of parallel bundles, and is marked by a superficial furrow which, how- 
ever, does not indicate a muscular division. It terminates on the medial surface 
of the stifle on a thi wide tendon which blends in front with that of the sartorius, 
below with the crural fascia. 
Relations.—Superficially, the skin and fascia, the penis or mammary gland, 
and the saphenous vessels and nerve; deeply, the pectineus, adductor, semimem- 
branosus and semitendinosus, and, at the middle of the femur, the femoral vessels; 
anteriorly, the sartorius. In the proximal third of the thigh the sartorius and gracili 
are separated by a triangular interval (femoral triangle), in which lie the deep in- 
guinal lymph glands and the femoral vessels. 
Blood-supply—Femoral and deep femoral arteries. 
Nerve-supply.—Obturator nerve. 
Sreconp LAYER 
1. Pectineus (Figs. 276, 288, 576).—This muscle is fusiform and extends from 
the anterior border of the pubis to the middle of the medial border of the femur. 
Origin.—The prepubic tendon, the accessory ligament, and the anterior border 
of the pubis. 
Insertion—The middle of the medial border of the femur, near the nutrient 
foramen. 
Action.—To adduct the limb and flex the hip joint. 
Structure-—The belly is cylindrical and contains little fibrous tissue. Its 
origin is perforated by the accessory ligament—from which many fibers arise— 
and is thus divided into two unequal parts. The large upper part arises largely 
from the prepubic tendon—only a small part gaining direct attachment to the 
pubis. The small lower part does not reach the bone. The insertion is pointed 
and tendinous. 
Relations.—Medially, the gracilis; laterally, the femur, the vastus medialis, 
the terminal part of the psoas major and illacus, and the deep femoral artery; an- 
teriorly, the sartorius, the femoral vessels, the saphenous nerve, and the deep in- 
guinal lymph glands; posteriorly, the adductor and obturator externus, and the 
obturator nerve (anterior division). 
Blood-supply.—Femoral and deep femoral arteries. 
Nerve-supply.—Obturator nerve. 
The femoral canal is exposed in the dissection of the preceding muscles (Figs. 
288, 290). It is bounded anteriorly by the sartorius, posteriorly by the pectineus, 
and laterally by the ilio-psoas and vastus medialis. Its medial wall is formed by 
the femoral fascia and the gracilis. Its upper or abdominal opening, the femoral 
ring (Lacuna vasorum), lies behind the medial part of the internal inguinal ring and 
is bounded anteriorly by the inguinal ligament, posteriorly by the anterior border 
of the pubis, and laterally by the tendon of the psoas minor. The canal termi- 
nates below at the insertion of the pectineus. It contains the deep inguinal lymph 
glands, the femoral artery and vein, and the saphenous nerve. 
2. Adductor! (Figs. 276, 288, 576).—This fleshy, prismatic muscle lies behind 
the pectineus and vastus medialis. It extends downward and forward from the 
ventral surface of the pelvis to the medial epicondyle of the femur. 
Origin.—The ventral surface of the pubis and ischium and the tendon of ori- 
gin of the gracilis. 
1Tt has been customary to describe two adductors—a parvus or brevis, and a longus or 
magnus. This division is partly artificial, and has been abandoned in the new nomenclature— 
a return to the views of Bourgelat and Girard. 
