1. The =intercostal lymph glands= (Lg. intercostales) are small and are
situated at the sides of the bodies of the thoracic vertebræ, in series
corresponding to the intercostal spaces. They receive afferents from the
vertebral canal, the spinal muscles, the diaphragm, intercostal muscles,
and pleura. The efferent vessels go to the thoracic duct.
In the young subject these glands are more numerous than in the adult,
and there are also glands along the dorsal face of the thoracic aorta
which seem to disappear later.
2. The =anterior mediastinal lymph glands= (Lg. mediastinales craniales)
(Fig. 428) are numerous. Some are situated on the course of the brachial
arteries and their branches; on the right side they are related deeply
to the trachea, on the left to the œsophagus also. They are variable in
size and disposition and are continuous in front with the prepectoral
glands. Other glands lie along the ventral face of the trachea on the
anterior vena cava and the right atrium of the heart; these are
continuous behind with the bronchial glands. A few glands usually occur
along the dorsal surface of the trachea, and there is often one at the
angle of divergence of the brachiocephalic trunk. The afferent vessels
come chiefly from the pleura, the pericardium, the heart, the thymus or
its remains, the trachea, and the œsophagus. Their efferent vessels pass
to the prepectoral glands and the thoracic duct.
The glands along the ventral face of the trachea are frequently
enlarged and usually pigmented in dissecting-room subjects. The left
recurrent nerve lies above them on the ventral face of the trachea.
3. The =bronchial lymph glands= (Lg. bronchiales) are grouped around the
terminal part of the trachea and the bronchi. One group lies on the
upper surface of the bifurcation of the trachea and is continued a short
distance backward under the œsophagus (Fig. 428). Others lie below the
trachea and bronchi and also occupy the angle between the aortic arch
and the pulmonary artery, concealing the left recurrent nerve and often
covering the vagus in this part of its course. Small glands occur along
the chief bronchi in the substance of the lungs (Lg. pulmonales). They
receive the deep and most of the superficial lymph vessels of the lungs,
and the efferents from the posterior mediastinal glands. Their efferent
vessels go to the thoracic duct and the anterior mediastinal glands. The
deep lymph vessels of the lung arise in plexuses which surround the
terminal bronchi and accompany the bronchi to the root of the lung. The
superficial vessels form a rich network under the pleura; most of them
pass to the bronchial glands.
The bronchial glands are commonly pigmented except in young subjects
and are often enlarged and indurated.
4. The =posterior mediastinal lymph glands= (Lg. mediastinales caudales)
are usually small and are scattered along the posterior mediastinum
above the œsophagus. They receive afferent vessels from the œsophagus,
mediastinum, diaphragm, and liver. The efferents go to the bronchial and
anterior mediastinal lymph glands, partly to the thoracic duct directly.
Sometimes one or two small glands are situated in the acute angle
between the posterior vena cava and the diaphragm.