THE ŒSOPHAGUS

This is much shorter, wider, and more dilatable than that of the horse.

Its average diameter (when moderately inflated) is about two inches (ca.

5 cm.), and its length in a large animal is about three to three and a

half feet (ca. 90 to 100 cm.). The wall is relatively thin, and the

muscular tissue is striped throughout. The latter consists of two strata

of spiral fibers, except near the stomach, where they are longitudinal

and circular. Fibers are continued into the wall of the stomach for some

distance. There are submucous glands in the first part of the tube.

There is no terminal dilatation, and no part in the abdominal cavity.

A very large mediastinal lymph gland lies above the posterior part of

the œsophagus and may, if enlarged, obstruct it (Fig. 289).

A text-book of veterinary anatomy · 第 498 / 1619 题