146 U.S. NATIONAL MUSEUM BULLETIN 2 73 



of the peroneus brevis in the tarsus and going to the head of the 

 metatarsal. 



Ventral Musculature 

 Coxofemoral Group 



PREPELVIC 



M. pectinevs: This is a triangular muscle which, arising by fleshy- 

 fibers from the iliopectineal line (fig. 36) in front of the insertion of 

 the external oblique, passes distallj'' into the thigh, forming the medial 

 side of the floor of the femoral triangle. The pectineus is inserted on 

 the upper fourth of the medial lip of the linea aspera in front of m. 

 adductor longus (fig. 40) and is divided into a medial and lateral half 

 by the nerve to the gracUis. Both parts are very thin near their 

 attachment. Sirena (1871) says that this ending takes place by a 

 tendon. This contrasts with my observations of a thin muscular 

 insertion upon the femur. 



Nerve supply: The lateral portion is innervated by a branch of 

 the femoral nerve which, after passing deep to the femoral vessels, 

 reaches the muscle on its deep surface. The medial receives a branch 

 from the anterior ramus of the obturator nerve. 



Function: Adduction and lateral rotation of the femur. 



M. obturatorius externus: This muscle is deep to all those found 

 in the angle between the femur and the innominate bone. It arises 

 by fleshy fibers from most of the ventral three-fourths of the obturator 

 foramen (fig. 36) . This includes the borders of the opening formed by 

 the body of the pubis, its two rami, and the lower ischial ramus. 

 Many of the fascicles have origin on the obturator membrane. The 

 bundles of the external obtiu-ator are directed dorsally to form a 

 flattened tendon which glides over the femoral surface of the ischium, 

 passes below and then behind the anatomical neck of the femur to 

 insertion in the rear of the trochanteric fossa (fig. 40). The muscle is 

 pierced by the posterior ramus of the obturator nerve. Sirena (1871) 

 points out that it is better developed than in man. 



Nerve supply: The posterior ramus of the obturator nerve. 



Function: Lateral rotation of the femur. 



M. addnctor longus: This is the most ventrally placed of all three 

 adductor muscles and lies in front of the brevis and magnus but 

 behind the pectineus. The adductor longus arises by muscular fibers 

 from (1) the iliopectineal line near the symphysis, (2) the femoral 

 surface of the pubic body and part of its lower ramus. This origin 

 lies between those of gracilis superficially and the external obturator 

 deeply (fig. 36). The muscle is composed of thick and fleshy bundles 

 connected by areolar tissue and easy to separate. Its fibers run disto- 



