1. The =submaxillary lymph glands= (Lg. submaxillares) (Figs. 437, 462)
are arranged in two elongated groups in the submaxillary space along
each side of the omo-hyoid muscles. The two groups are in apposition in
front of the insertion of these muscles and diverge posteriorly in the
form of a =V=, extending backward about four or five inches (ca. 10 to
12 cm.). They are covered by the skin and a thin layer of fascia and
panniculus, and are therefore palpable. Anteriorly they are firmly
attached to the mylo-hyoidei, but otherwise they are rather movable in
the normal state. Each group is related externally to the external
maxillary artery and the anterior belly of the digastricus, below to the
external maxillary vein, and above to the lingual and sublingual veins.
They receive =afferent vessels= from the lips, nostrils, nasal region,
cheeks, the anterior part of the tongue, the jaws, the floor of the
mouth, and the greater part of the hard palate and nasal cavity. The
=efferent vessels= pass to the anterior cervical and pharyngeal glands.
The superficial lymph vessels of the face converge to twelve to
fifteen trunks which turn around the lower border of the jaw with the
facial vessels. Those of the lips form plexuses at the commissures.
The nasal mucous membrane is richly supplied with lymph vessels which
accompany the veins; posteriorly they communicate with the subdural
and subarachnoid spaces and send efferents to the pharyngeal and
anterior cervical glands.
2. The =pharyngeal lymph glands= (Figs. 436, 437, 569) may consist of
two groups. One lies on the lateral surface of the pharynx along the
course of the external carotid artery. These glands are related
externally to the stylo-maxillaris and digastricus and often to the
submaxillary gland also, above to the guttural pouch. Other glands (Lg.
retropharyngeales) are commonly found on the guttural pouch along the
course of the internal carotid artery. They lie below the artery and are
covered by the aponeurosis of the mastoido-humeralis and the cervical
end of the submaxillary gland.
They receive afferent vessels from the cranium, the posterior part of
the tongue, the soft palate, pharynx, guttural pouch, larynx, posterior
part of the nasal cavity, and efferents from the submaxillary glands.
3. The =anterior cervical lymph glands= (Lg. cervicales craniales) are
situated chiefly along the course of the common carotid artery in the
vicinity of the thyroid gland, under cover of the cervical angle of the
parotid gland. Some occur between the thyroid and the submaxillary
salivary gland, others above and partly upon the thyroid. They are
related deeply to the posterior part of the larynx, the trachea, the
thyroid gland, and the œsophagus; below to the external maxillary vein
and the outer border of the omo-hyoideus.[177]
These glands are variable. Often there are none in front of the
thyroid and the group may extend back a considerable distance along
the course of the carotid artery.
Their afferents are deep lymph vessels from the head, the pharynx,
larynx, guttural pouch, and thyroid gland, and efferents from the
submaxillary and pharyngeal glands. Their efferent vessels go to the
middle and posterior cervical glands.
4. The =middle cervical lymph glands= (Lg. cervicales mediæ) form an
inconstant group situated a little in front of the middle of the neck on
the trachea below the carotid artery. The group is usually small and in
some cases is absent, being replaced by a number of glands occurring at
intervals along the course of the carotid artery. In other subjects the
group consists of several glands of considerable size. They are
intercalated in the course of the tracheal lymph ducts.
5. The =posterior cervical= or =prepectoral lymph glands= (Lg.
cervicales caudales) form a large group below the trachea at the
entrance to the thorax (Fig. 466). They occupy the interstices between
the vessels and muscles and extend forward a variable distance on the
ventral aspect of the trachea. They are covered by the panniculus and
sterno-cephalicus. Their afferent vessels come from the head, neck,
thorax, and thoracic limb. They receive efferent ducts of the anterior
and middle cervical, prescapular, and axillary glands. Their efferents
go to the thoracic duct on the left, to the right lymphatic duct on the
right, or open directly into the vena cava.
6. The =prescapular= or =superficial cervical lymph glands= (Lg.
cervicales superficiales) lie on the anterior border of the anterior
deep pectoral muscle, in relation to the omo-hyoideus internally and the
mastoido-humeralis externally (Figs. 431, 441, 466). They are on the
course of the ascending branch of the inferior cervical artery. They
receive afferents from the neck, breast, shoulder, and arm. Their
efferents pass to the prepectoral glands.
The =tracheal ducts=, right and left (Ductus trachealis dexter,
sinister), are collecting trunks for the lymph of the head and neck.
They lie on the trachea in relation to the carotid arteries. The right
one goes to the prepectoral glands or to the right lymphatic duct, the
left one to the terminal part of the thoracic duct.