Fig. 62. Front View of the Neck, Deep Layer. Child. 



Child a few months old; head inclined backwards. On the left side, the super- 

 ficial structures are displayed after removal of the Platysma; on the right side, 

 the Sterno-Cleido-Mastoid has been cut off near its attachment. The Sternum 

 has been removed between the middle of the Manubrium and the base of the 

 Xiphoid, and with it the 2nd, p'd, 4th, ^th, 6th Costal Cartilages. 



The chief difference in this part between the adult and the child, is the 

 Thymus which is large in the latter. This gland continues its development till 

 the 2nd year, then degenerates or remains stationary till puberty. After puberty, 

 it disappears rapidly; its lobes undergo fatty degeneration; there are, however, 

 alwaj's masses of fat containing a few . remains of this glandular tissue present 

 even in the adult. The shape of the gland varies much. There are usually 

 2 longitudinally placed lobes which are pointed above. The limits of the gland 

 are: the level of the 3rd rib, and the lower border of the Thyreoid Gland. Below 

 the Thymus is in relation with the Pericardium, its middle portion is covered by 

 the Sternum ; between its outer portion and the thoracic wall, the pleural cavity 

 and the lungs find their way. Above the pericardium, this gland is an anterior 

 relation of the Arch of the Aorta, Superior Vena Cava and Innominate Veins. 

 At a still higher level, it lies on the Trachea, being separated from the skin by 

 Sterno-Hyoid and Sterno-Thyreoid Muscles; at this point it becomes an internal 

 relation to the Innominate Artery, Carotid Artery and Internal Jugular Vein. 



This figure also shews some of the Lymphatic glands of the Neck 

 and Thorax. 



The chief lymphatic channel, the Thoracic Duct, commences in the ab- 

 domen, usually opposite the ist Lumbar Vertebra (Receptaculum Chyli, cf. Fig. 141). 

 It runs vertically upwards on the right of the Aorta, passing through the Dia- 

 phragm, and lying in the Thorax between the Aorta and Great Azygos Vein. 

 Opposite the body of the 7th Cervical Vertebra it arches over the left Subclavian 

 Artery and opens into the left Subclavian Vein (cf. Fig. 67). The corresponding 

 structure on the right is the short right Lymphatic Duct which opens into the 

 right Subclavian Vein. The great lymphatic channel on the right side is formed 

 by the junction of the Bronchial, Mediastinal, Jugular and Subclavian Lymphatics; 

 on the left, the Thoracic Duct receives the left Jugular and Subclavian Lymphatics 

 which carry the lymph from the head and upper extremity. These last mentioned 

 channels may open separately into the veins. 



Between the 2 bellies of the Digastric the Submental Glands are shewn ; 

 on the Submaxillary Gland, the Submaxillary Lymphatic Glands are visible; at 

 a lower level on the Internal Jugular Vein the Superficial Cervical Glands are seen 

 (more about this group in Fig. 63, text). 



On the left side, some of the Inferior Deep Cervical Glands (cf. Fig. 115, 

 text), and finally the Sternal Glands are shewn. These lie near the Internal 

 Mammary Artery and its Venae Comites but are not found in all the interspaces. 

 Their efferent vessels go to the mediastinal glands, to the great lymphatic ducts 

 and to the lymphatics of the neck (cf. Fig. 115). 



