chain along the internal jugular vein, beneath the sterno-mastoid muscle.  They drain the various groups of glands which lie nearer the surface, also the interior of the skull, the larynx, trachea, thyreoid, and lower part of the pharynx, and pour their lymph into the main trunks at the root of the neck.  Belonging to this group is one large gland (the tonsillar gland) which lies behind the posterior belly of the digastric, and rests in the angle between the internal jugular and common facial veins.  It is commonly enlarged in affections of the tonsil and posterior part of the tongue.  In the same group are three or four glands which lie entirely under cover of the upper end of the sterno-mastoid muscle, and surround the accessory nerve before it perforates the muscle.  The deep cervical glands are commonly infected by tubercle and also by epithelioma secondary to disease in the tongue or throat. The inferior deep cervical (supra-clavicular) glands lie in the posterior triangle, above the clavicle.  They receive lymph from the lowest cervical glands, from the upper part of the chest wall, and from the highest axillary glands.  They are frequently infected in cancer of the breast; those on the left side also in cancer of the stomach.  The removal of diseased supra-clavicular glands is not to be lightly undertaken, as difficulties are liable to ensue in connection with the thoracic duct, the pleura, or the junction of the subclavian and internal jugular veins. The retro-pharyngeal glands lie on each side of the median line upon the rectus capitis anticus major muscle and in front of the pre-vertebral layer of the cervical fascia.  They receive part of the lymph from the posterior wall of the pharynx, the interior of the nose and its accessory cavities, the auditory (Eustachian) tube, and the tympanum.  When they are infected with pyogenic organisms or with tubercle bacilli, they may lead to the formation of one form of retro-pharyngeal abscess.

#Upper Extremity.#—­The epi-trochlear and cubital glands vary in number, that most commonly present lying about an inch and a half above the medial epi-condyle, and other and smaller glands may lie along the medial (internal) bicipital groove or at the bend of the elbow.  They drain the ulnar side of the hand and forearm, and pour their lymph into the axillary group.  The epi-trochlear gland is sometimes enlarged in syphilis. The axillary glands are arranged in groups:  a central group lies embedded in the axillary fascia and fat, and is often related to an opening in it; a posterior or subscapular group lies along the line of the subscapular vessels; anterior or pectoral groups lie behind the pectoralis minor, along the medial side of the axillary vein, and an inter-pectoral group, between the two pectoral muscles.  The axillary glands receive lymph from the arm, mamma, and side of the chest, and pass it on into the lowest cervical glands and the main lymph trunk.  They are frequently the seat of pyogenic, tuberculous, and cancerous infection, and their complete removal is an essential part of the operation for cancer of the breast.