which is sent to the right portion of the transverse colon, the other to
the left. In its course, the _superior hemorrhoidal artery_ divides into
two branches, which enter the intestine from behind, and embrace it on
all sides, almost to the anus.

The _Thoracic Duct_ is the principal trunk of the absorbent system, and
the canal through which much of the chyle and lymph is conveyed to the
blood. It begins by a convergence and union of the lymphatics on the
lumbar vertebræ, in front of the spinal column, then passes upward
through the diaphragm to the lower part of the neck, thence curves
forward and downward, opening into the subclavian vein near its junction
with the left jugular vein, which leads to the heart.

[Illustration: Fig. 32.
_c, c_. Right and left subclavian veins. _b_.
Inferior vena cava. _a_. Intestines. _d_. Entrance
of the thoracic duct into the left
subclavian vein. _4_. Mesenteric glands,
through which the lacteals pass to the
thoracic duct.]

[Illustration: Fig. 33.
The inferior surface of the liver. 1. Right lobe.
2. Left lobe. 3. Gall-bladder.]

The _Liver_, which is the largest gland in the body, weighs about four
pounds in the adult, and is located chiefly on the right side,
immediately below the diaphragm. It is a single organ, of a dark red
color, its upper surface being convex, while the lower is concave. It
has two large lobes, the right being nearly four times as large as the