LYMPHATIC SYSTEM OF THE OX AND SHEEP 725 
The costo-cervical lymph gland (Lg. costo-cervicalis)! is situated lateral to the 
trachea and cesophagus and dorsal to the carotid artery and the vago-sympathetic 
trunk. It lies usually just in front of the first rib, under cover of the scalenus 
muscle, but it may be partly medial to the first rib. Its length varies from about 
half an inch to an inch or more (1.5-3 em.). Its afferent vessels come from the 
muscles of the neck and shoulder, the costal pleura, the trachea, and the intercostal 
and anterior mediastinal glands. The efferent vessels on the right side usually go 
to the right tracheal duct or join the efferent vessel of the prescapular gland; on the 
left they go most often to the end of the thoracic duct, but are very variable. 
The tracheal lymph ducts (Ductus tracheales), right and left, are formed 
essentially by the confluence of efferent vessels from the atlantal gland. They 
usually receive efferent vessels from the cervical, costo-cervical, and prescapular 
glands. The ducts pass along each side of the trachea and cesophagus; the right 
one usually opens into the right common jugular vein; the left one joins the terminal 
part of the thoracic duct or opens into the left common jugular vein. 
These ducts are very variable in regard to formation affluents, and termination. There 
may be an accessory tracheal duct, which receives part of the lymph vessels that otherwise go to 
the chief duct; this accessory duct runs a variable distance along the neck practically parallel 
with the chief duct, and unites with the latter. 
A short right lymphatic duct may be formed by the junction with the terminal 
part of the right tracheal duct of efferent vessels from the right cervical, costo-cer- 
vical, and prescapular lymph glands. It also usually receives an efferent vessel 
from the anterior sternal lymph gland. 
The prescapular or posterior superficial cervical lymph gland (Lg. cervicalis 
superficialis caudalis) is situated at the anterior border of the supraspinatus, a little 
above the level of the shoulder joint; it is covered by the omo-transversarius and 
brachiocephalicus muscle. It is elongated and may attain a length of four or five 
inches (ca. 10-12 em.) and a width of an inch or more (ca. 3 cm.). Its deep face 
has a long and distinct hilus. It receives afferents from the skin of the neck, 
shoulder, part of the ventral and lateral surfaces of the thorax, and the thoracic 
limb; from the muscles of the shoulder-girdle, and from the external scapular 
muscles; from the tendons of the muscles of the forearm and digit and the fascia 
of the forearm; from the joints of the carpus and digit. The efferent vessel de- 
scends over the scalenus muscle and opens on the right side into the end of the right 
tracheal duct, on the left into the terminal part of the thoracic duct or the left 
tracheal duct. 
In one case Baum found two efferent vessels on the right side: one opened into the end of 
the tracheal duct, the other went to a posterior cervical gland. 
A chain of small nodes, five to ten in number, extends along the border of the supraspinatus, 
dorsal to the prescapular gland, and covered by the trapezius and omo-transversarius. These 
nodes, termed by Baum lymphoglandul cervicales nuchales, are in most cases dark red in color, 
and most of them are hemolymph glands. But some are lymph glands, since they receive afferent 
vessels from adjacent muscles and send efferent vessels to the prescapular lymph gland or to 
another gland of the group. 
The intercostal lymph glands are situated in the dorsal ends of the intercostal 
spaces, on the course of the intercostal vessels, and embedded in fat. Most of them 
are small, but some may be nearly an inch (ca. 2 em.) long. Not all of the spaces 
contain glands, and quite exceptionally two may occur in one space. Associated 
with them are hemolymph glands. The afferent vessels come chiefly from the 
intercostal and spinal muscles, the serrati, latissimus dorsi, trapezius, subscapularis, 
longus colli, obliquus abdominis externus; from the costal pleura and the peri- 
toneum; from the thoracic vertebre and the ribs. The efferent vessels go to the 
mediastinal lymph glands. 
1 This gland has been included in the posterior cervical group, but forms a connecting link, 
as it were, between the cervical and mediastinal glands. Baum has given it the above name and 
has shown that it receives lymph vessels from the pleura. 
