_Description._—The ischium is smaller than the ilium and is a flattened, triangular-shaped bone, thickest where it forms the posterior part of the acetabulum, becoming thinner and broader as it extends backward. Posteriorly it forms the caudal extension. The inferior border is turned slightly outward and is fused with the pubis. Between these bones there is located the large oval _ischiadic foramen_, through which passes the ischiadic nerve. This bone aids the ilium in the formation of the obturator foramen through which passes the tendon of the internal obturator muscle. The lower part of the ischium which separates the ischiadic foramen from the obturator foramen is called the _ramus ascendens ossis ischii_. =The Pubis.= _Location._—The pubis is located along the inferior margin of the ischium and extends further back than the posterior border of the ischium. _Description._—The pubis is a long, slender, rib-like bone. It forms the lower and front portion of the acetabulum. The ischiadic foramen formed by the ischium and pubis is single and nearly circular in fowls, double in pigeons, and in geese and ducks it is elongate. THE HIND LIMB (Fig. 4, Nos. 35, 47, 48, 49, 50, 51, 52, and 53; Fig. 12) The pelvic, or hind, limb supports the body. The bones of each leg are the femur, which constitutes the thigh, the tibia and the fibula, which represents the leg, and the metatarsus and the phalanges, which form the foot. =The Femur= (Fig. 12, _A_ and _B_). _Location._—The femur, or os femoris, the first bone of the hind extremity, extends obliquely downward and forward, articulating with the acetabulum above and the tibia, the fibula, and the patella below. _Description._—The femur, one of the largest, thickest, and strongest bones of the body, belongs to the class of cylindrical bones, and presents for examination a shaft and two extremities. The superior, or proximal extremity, is provided with a head, caput femoris; the neck, collum femoris; and the trochanter. The head is relatively small, and is marked by a depression above for the round ligament which fills the cavity in the acetabular wall. Its axis is nearly at right angles with the shaft. A neck joins it to the body at the proximal end. External to the head of the femur is the _trochanter_. The trochanter presents an outer convexity over which the tendon of the gluteus maximus extends to become inserted below. The _trochanteric ridge_, which is opposite the articular head, presents an outer flattened surface which possesses impressions for muscular attachments. The _trochanteric fossa_, or fossa trochanterica, is shallow. The _shaft_, or _corpus femoris_, is shorter than the tibia, is in general cylindrical, bent forward, and the lower half is flattened and expanded transversely. A nutrient foramen is located in the median portion of the shaft. The shaft shows muscular linear ridges.