(_a_) _A lingual artery supplying the tongue._
(_b_) _A carotid artery, running round the side of the œsophagus,
and supplying the head. At its origin it is slightly swollen into
the carotid gland._
2. _The systemic arches run backwards on each side of the body, and
meet posteriorly to form the dorsal aorta. Each systemic arch gives
off_:--
(_a_) _A subclavian artery to the shoulder and fore-limb._
(_b_) _An occipito-vertebral artery to the head and the vertebral
column._
(_c_) _An œsophageal artery to the dorsal wall of the œsophagus._
(_d_) _A laryngeal artery to the larynx._
_At the point where the dorsal aorta is formed, note the origin of
the cœliaco-mesenteric artery which sends branches to the stomach,
liver, intestine, and spleen._
_Trace the dorsal aorta backwards and note that it passes between
the kidneys, to each of which it gives off four renal arteries and
then it divides posteriorly into an iliac artery to each leg. The
iliac artery is continued backwards as the femoral artery in the
leg._