ILIUM. 229 



cave behind; bounded above bj the crest, below by the upper border of the 

 acetabulum ; in front and behind, by the anterior and posterior borders. This 

 surface is crossed in an arched direction by three semicircular lines, the supe- 

 rior, middle, and inferior curved lines. The superior curved line, the shortest 

 of the three, commences at the crest, about two inches in front of its posterior 

 extremity ; it is at first distinctly marked, but as it passes downwards and out- 

 wards to the upper part of the great sacro-sciatic notch, where it terminates, it 

 becomes less marked, and is often altogether lost. The rough surface included 

 between this line and the crest, affords attachment to part of the Gluteus 

 Maximus above, a few fibres of the Pyriformis below. The middle curved 

 line, the longest of the three, commences at the crest, about an inch behind its 

 anterior extremity, and, taking a curved direction downwards and backwards, 

 terminates at the upper part of the great sacro-sciatic notch. The space between 

 the middle and superior curved lines and the crest is concave, and affords 

 attachment to the Gluteus Medius muscle. Near the central part of this line 

 may often be observed the orifice of a nutrient foramen. The inferior curved 

 line, the least distinct of the three, commences in front at the upper part of the 

 anterior inferior spinous process, and taking a curved direction backwards and 

 downwards, terminates at the anterior part of the great sacro-sciatic notch. 

 The surface of bone included between the middle and inferior curved lines is 

 concave from above downwards, convex from before backwards, and affords 

 attachment to the Gluteus Minimus muscle. Beneath the inferior curved line, 

 and corresponding to the upper part of the acetabulum, is a smooth eminence 

 (sometimes a depression), to which is attached the reflected tendon of the Kectus 

 Femoris muscle. 



The internal surface (Fig. 165) of the ilium is bounded above by the crest, 

 below by a prominent line, the linea ilio-pectinea, and before and behind by 

 the anterior and posterior borders. It presents anteriorly a large smooth con- 

 cave surface called the internal iliac fossa, or venter of the ilium, which lodges 

 the Iliacus muscle, and presents at its lower part the orifice of a nutrient canal. 

 Behind the iliac fossa is a rough surface, divided into two portions, a superior 

 and an inferior. The inferior or auricular portion, so called from its resem- 

 blance in shape to the ear, is coated with cartilage in the recent state, and 

 articulates with a similar shaped surface on the side of the sacrum. The supe- 

 rior portion is concave and rough, for the attachment of the posterior sacro-iliac 

 ligaments. 



The crest of the ilium is convex in its general outline and sinuously curved, 

 being bent inwards anteriorly, outwards posteriorly. It is longer in the female 

 than in the male, very thick behind, and thinner at the centre than at the 

 extremities. It terminates at either end in a prominent eminence, the anterior 

 superior and posterior superior spinous process. The surface of the crest is 

 broad, and divided into an external lip, an internal lip, and an intermediate 

 space. To the external lip is attached the Tensor Vagina3 Femoris, Obliquus 

 Externus Abdominis, and Latissimus Dorsi, and by its whole length the fascia 

 lata ; to the interspace between the lips, the Internal Oblique ; to the 'internal 

 lip, the Transversalis, Quadratus Lumborum, and Erector Spinae. 



The anterior border of the ilium is concave. It presents two projections sepa- 

 rated by a notch. Of these, the uppermost, situated at the junction of the crest 

 and anterior border, is called the anterior superior spinous process of the ilium, 

 the outer border of which gives attachment to the fascia lata, and the origin of 

 the Tensor Vaginae Femoris ; its inner border, to the Iliacus Internes ; whilst 

 its extremity affords attachment to Poupart's ligament, and the origin of the 

 Sartorius. Beneath this eminence is a notch which gives attachment to the 

 Sartorius muscle, and across which passes the external cutaneous nerve. Below 

 the notch is the anterior inferior spinous process, which terminates in the upper 

 lip of the acetabulum ; it gives attachment to the straight tendon of the Rectus 

 Femoris muscle. On the inner side of the anterior inferior spinous process is a 



