OSTEOLOGY AND SYNDESMOLOGY. 36. 
‘ 
cuboid, scaphoid, and three cuneiform ; the metatarsus of five, and the toes, 
of fourteen: thirty-two bones in all. | 
1. THE PELVIS (pl. 122, fig. 8, K K, pl. 123, figs. 48, 45) is the irregular, . 
circular shaped, bony ring at the lower end of the trial formed by the 
sacrum and coccyx posteriorly, and by the ossa innominata laterally and 
anteriorly ; it contains some of the abdominal viscera and many of the, 
urinary and generative organs; it also supports the spinal column above, 
and transmits the weight to the thigh bones, on which it rests below. The 
sacrum and coccyx have already been jell As each os innominatum. 
(pl. 122, jig. 3, K) is divisible in early life into three bones, the ilium, 
ischium, and Bee. uniting to form the socket for the head of the thigh - 
bone, we shall first consider these separately, and then as united into one 
bone, as in the adult. a 
a. The individual bones of the Pelvis. The os ilium (pl. 128, fig. 48°) 
is situated at the upper and outer part of the pelvis, and forms that projec-. 
tion commonly called the hip. It is broad, flat, and triangular, the base . 
above bounded by a semicircular crest, which ends before and behind in 
processes or tubercles named spinous; the apex below forming the upper 
and outer part of the acetabulum or socket; it may be divided into the, 
body, ala, and processes. The body is the ee a narrowed portion ; the 
ala is the broad, fan-like, semicircular portion which ascends from the body, ‘ 
inclining eae and a little forwards; the external surface, or dorsum, st ’ 
rough sind irregularly convex and concave, with a pee ieceele concavity; 
fies the acetabulum (external ilia fossa) and two curved semicircular. 
lines, a superior’and an inferior. The internal surface of the ala is divided 
into three parts: one, superior and anterior, is the iliac fossa ;. the second 
forms about the posterior third of the bone; and the third is smooth and 
small, and is the only portion of the ilium that enters into the side of the 
true pelvis. It is separated from the iliac fossa by a rounded edge (called 
the ilio-pectineal line), continuous behind with the promontory of the. 
sacrum, and before with a sharper ridge on the pubes. The processes of 
the ilium are, first, the crest (pl. 123, fig. 48°), forming the upper border. 
of the ala; Sea. the anterior superior spine, at the anterior extremity of 
this crest ; ees is a notch between this and the third process, the anterior’. 
inferior spine. Internal to this space is a superficial groove, bounded inter-. 
nally by the clo-pectineal eminence, which is common to and formed by the 
union of the ilium and pubes. Fourth, the posterior superior spine is the. 
posterior termination of the crest ; and ed from this by a notch is the 
fifth process, the posterior inferior spine. ; 
The ischiuwm (pl. 122, fig. 4”°) is placed. at the nee outer, and back 
part of the pelvis, and presents a body and processes. The body forms the 
outer, lower, and back portion of the acetabulum, constituting more than 
two fifths of it. The processes are, first, the spine (jig. 4"), arising from_ 
near the middle of the posterior part, below the sacro-sciatic notch. Be- 
tween this and the second process is the pulley round which the tendon. of 
the obturator muscle turns. This next process is the tuberosity or tuber 
isch (fig. 4°). On this rough aud broad process the body rests when in. 
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