_1_, Ilium; _2_, femur; _3_, tuber ischii; _4_, sacro-sciatic lig.;
_5_, sacral region; _6_, tail; _7_, penis; _8_, anus; _9_, rectum;
_a_, sacro-coccygeus superior; _b_, sacro-coccygeus accessorius;
_c_, coccygeus; _d_, sacro-coccygeus inferior; _e_, retractor ani;
_f_, _f′_, sphincter ani externus; _g_, retractor penis; _h_,
bulbo-cavernosus; _i_, transversus perinei (?); _k_, _m_,
ischio-urethrales; _l_, ischio-cavernosus; _n_, tendon of obturator
internus; _o_, gemellus; _p_, urethral muscle. (After Ellenberger,
in Leisering’s Atlas.)
]
The =psoas minor= arises on the last thoracic and first four or five
lumbar vertebræ, and is inserted into the ilio-pectineal line.
The =psoas major= is short, arising from the last four lumbar vertebræ.
The outer head of the =iliacus= is small, while the inner head is large
and fuses with the psoas major.
The =quadratus lumborum= is well developed, and extends laterally beyond
the outer edge of the ilio-psoas. It arises from the last four ribs and
the lumbar transverse processes, and ends on the pelvic surface of the
wing of the ilium.
The =tensor fasciæ latæ= consists of two parts. The anterior part is
long and rounded; the posterior is shorter and fan-like.
The =gluteus superficialis= is small. It arises on the sacrum, first
coccygeal vertebræ, and sacro-sciatic ligament. It is inserted below and
behind the trochanter major of the femur, on the outer branch of the
linea aspera.
The =gluteus medius= has no lumbar portion. It is inserted into the
trochanter major by a strong tendon.
The =gluteus profundus= is broad and fan-shaped. It arises on the
superior ischiatic spine and on the ilium as far forward as the gluteal
line, and is inserted into the trochanter major below the medius.
The =pyriformis= is not blended with the gluteus medius. It arises from
the border of the sacrum and from the sacro-sciatic ligament, and ends
on the trochanter major.
The =biceps femoris= has two heads of origin which soon fuse. The larger
head arises from the sacro-sciatic ligament and tuber ischii, the
smaller one from the tuber ischii. The aponeurosis of insertion ends on
the patella, the patellar ligament, and the tibial crest. There is also
a tendinous band, which comes from the deep face of the muscle and
terminates at the tarsus, as in the horse.
The =abductor cruris posterior= may be regarded as an accessory head of
the biceps femoris. It is a thin, muscular band which arises on the
sacro-sciatic ligament, passes downward between the biceps and
semimembranosus, and ends by blending with the former.
The =semitendinosus= arises from the tuber ischii only. It ends as in
the horse.
[Illustration: